methylene blue photocatalytic degradation under visible...

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Research Article Methylene Blue Photocatalytic Degradation under Visible Irradiation on In 2 S 3 Synthesized by Chemical Bath Deposition William Vallejo, Carlos Díaz-Uribe, and Kathy Rios Grupo de Fotoqu´ ımica y Fotobiolog´ ıa, Universidad del Atl´ antico, Km 7 Antigua V´ ıa Puerto Colombia, Barranquilla, Colombia Correspondence should be addressed to William Vallejo; [email protected] Received 2 December 2016; Revised 16 February 2017; Accepted 28 February 2017; Published 16 April 2017 Academic Editor: Leonardo Palmisano Copyright © 2017 William Vallejo et al. is is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. In this work, we synthesized In 2 S 3 powder through chemical bath deposition method (CBD) in acid medium; we used thioacetamide as sulphide source and InCl 3 as indium ion source. X-ray diffraction, diffuse reflection, and Raman spectroscopy measurements were used for In 2 S 3 powder physicochemical characterization. Optical analysis indicated that In 2 S 3 was active in the visible region of electromagnetic spectrum; it had a band gap of 2.47 eV; the diffraction patterns and Raman spectroscopy suggested that powder had polycrystalline structure. Furthermore, we also studied the adsorption process of methylene blue (MB) on In 2 S 3 powder; adsorption studies indicated that the Langmuir model describes experimental data. Finally, photocatalytic degradation of MB was studied under visible irradiation in aqueous solution; besides, pseudo-first-order model was used to obtain kinetic information about photocatalytic degradation; results indicated that the powder catalyst reduces 26% concentration of MB under visible irradiation. 1. Introduction Nowadays, a subject of great research worldwide is associated with study of different ways to degrade pollutants (e.g., biological and chemical) present into water sources, because they have a negative impact on both quality ground (internal) and surface level of water reserves last reports indicate that more than 2 million tons of pollutants are generated daily in the planet; furthermore, about 1800 millions of people around the world are supplied by a source of water contaminated by biological or chemical pollutant [1]. is is a serious environmental problem and currently is part of an objective study of different research institutes and government agen- cies. e World Health Organization (WHO) launched an international plan to evaluate water treatment technologies to establish work policy and to analyze new WHO criteria [2, 3]. Conventional water decontamination processes contain (a) the possible self-purification (waterfalls and streams high speed), (b) desorption air, (c) ozone, (d) hydrogen peroxide, (e) potassium permanganate solutions (chemical oxidation), and (f) aerobiological methods; some of these processes achieve the mineralization of species [4, 5]. Precipitation of heavy metal ions is oſten performed by the addition of coagulants and flocculants; besides, activated carbon and other adsorbents can be used [6–8]. However, these conven- tional methods do not degrade common recalcitrant organic pollutants in water, such as dyes, antibiotics, and pesticides. Effective removal from aquatic environments is necessary for water purification and conservation and maintaining human and ecological health [9]. Heterogeneous photocatalysis (HP) is an option to degrade different recalcitrant pollutants, because HP is not a selective process; this methodology could act on almost any contaminant under suitable conditions [10]. Conventionally, photocatalyst most studied in this field is titanium dioxide (TiO 2 ); however despite all the character- istics, TiO 2 has three main drawbacks: (a) fast recombination rate of photogenerated electron-hole pair, (b) low quantum yield in the photocatalytic reactions in aqueous solutions, and (c) high band gap value (3.2eV, photocatalytic active only under UV-irradiation) [11]. Today, it is common to modify both bulk and surface properties of TiO 2 to solve these problems; some options involve the following: (a) noble metal loading is used to reduce recombination rate of electron- hole pair; (b) both ion implantation and nonmetal doping are applied to reduce band gap of the TiO 2 ; and (c) sensitization occurs by absorption of natural and/or synthetic organic dyes. Hindawi Advances in Physical Chemistry Volume 2017, Article ID 6358601, 5 pages https://doi.org/10.1155/2017/6358601

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Page 1: Methylene Blue Photocatalytic Degradation under Visible ...downloads.hindawi.com/archive/2017/6358601.pdf · ResearchArticle Methylene Blue Photocatalytic Degradation under Visible

Research ArticleMethylene Blue Photocatalytic Degradation under VisibleIrradiation on In2S3 Synthesized by Chemical Bath Deposition

William Vallejo Carlos Diacuteaz-Uribe and Kathy Rios

Grupo de Fotoquımica y Fotobiologıa Universidad del Atlantico Km 7 Antigua Vıa Puerto Colombia Barranquilla Colombia

Correspondence should be addressed to William Vallejo williamvallejomailuniatlanticoeduco

Received 2 December 2016 Revised 16 February 2017 Accepted 28 February 2017 Published 16 April 2017

Academic Editor Leonardo Palmisano

Copyright copy 2017 William Vallejo et alThis is an open access article distributed under the Creative Commons Attribution Licensewhich permits unrestricted use distribution and reproduction in any medium provided the original work is properly cited

In this work we synthesized In2S3 powder through chemical bath deposition method (CBD) in acid medium we usedthioacetamide as sulphide source and InCl3 as indium ion source X-ray diffraction diffuse reflection and Raman spectroscopymeasurements were used for In2S3 powder physicochemical characterization Optical analysis indicated that In2S3 was active in thevisible region of electromagnetic spectrum it had a band gap of 247 eV the diffraction patterns and Raman spectroscopy suggestedthat powder had polycrystalline structure Furthermore we also studied the adsorption process of methylene blue (MB) on In2S3powder adsorption studies indicated that the Langmuir model describes experimental data Finally photocatalytic degradationof MB was studied under visible irradiation in aqueous solution besides pseudo-first-order model was used to obtain kineticinformation about photocatalytic degradation results indicated that the powder catalyst reduces 26 concentration of MB undervisible irradiation

1 Introduction

Nowadays a subject of great research worldwide is associatedwith study of different ways to degrade pollutants (egbiological and chemical) present into water sources becausethey have a negative impact on both quality ground (internal)and surface level of water reserves last reports indicate thatmore than 2 million tons of pollutants are generated daily inthe planet furthermore about 1800millions of people aroundthe world are supplied by a source of water contaminatedby biological or chemical pollutant [1] This is a seriousenvironmental problem and currently is part of an objectivestudy of different research institutes and government agen-cies The World Health Organization (WHO) launched aninternational plan to evaluate water treatment technologies toestablish work policy and to analyze newWHO criteria [2 3]

Conventional water decontamination processes contain(a) the possible self-purification (waterfalls and streams highspeed) (b) desorption air (c) ozone (d) hydrogen peroxide(e) potassium permanganate solutions (chemical oxidation)and (f) aerobiological methods some of these processesachieve the mineralization of species [4 5] Precipitationof heavy metal ions is often performed by the addition of

coagulants and flocculants besides activated carbon andother adsorbents can be used [6ndash8] However these conven-tional methods do not degrade common recalcitrant organicpollutants in water such as dyes antibiotics and pesticidesEffective removal from aquatic environments is necessary forwater purification and conservation and maintaining humanand ecological health [9] Heterogeneous photocatalysis (HP)is an option to degrade different recalcitrant pollutantsbecause HP is not a selective process this methodology couldact on almost any contaminant under suitable conditions [10]Conventionally photocatalyst most studied in this field istitanium dioxide (TiO2) however despite all the character-istics TiO2 has three main drawbacks (a) fast recombinationrate of photogenerated electron-hole pair (b) low quantumyield in the photocatalytic reactions in aqueous solutions and(c) high band gap value (32 eV photocatalytic active onlyunder UV-irradiation) [11] Today it is common to modifyboth bulk and surface properties of TiO2 to solve theseproblems some options involve the following (a) noblemetalloading is used to reduce recombination rate of electron-hole pair (b) both ion implantation and nonmetal doping areapplied to reduce band gap of the TiO2 and (c) sensitizationoccurs by absorption of natural andor synthetic organic dyes

HindawiAdvances in Physical ChemistryVolume 2017 Article ID 6358601 5 pageshttpsdoiorg10115520176358601

2 Advances in Physical Chemistry

0

20

40

60

80

100

120

140

20 30 40 50 60 70

2휃 (degree)

(au

)

(311

)

In2S3 (JCPDS number 65-0459)

(222

)

(400

)

(511

)

(440

)

(533

)

(444

)Figure 1 XRDpattern of In2S3 powder synthesized byCBDprocess

Thesemethodologies improve photoactivity of TiO2 at visibleregion of electromagnetic spectrum [12] Another alternativeincludes change of TiO2 for other semiconductor havinglower band gap value and potential photocatalytic activityIn2S3 is considered a promising material due to its chemicalstability and its activity in visible range of the electromagneticspectrum it has three different crystalline structures andit has potential photocatalytic activity [13ndash15] It has beenreported that this compound exhibits photocatalytic activityin the degradation of aqueous formic acid andmethyl orangeunder visible light irradiation [16 17]

The aim of this study is to evaluate the photocatalyticactivity of In2S3 synthesized by CBD in the degradation ofmethylene blue as a potential alternative in photocatalysis

2 Experimental

21 Compound Synthesis Powder of In2S3 was synthesized byCBDprocess from solution containing thioacetamide (Schar-lau) (TA 0350M) and indium chloride (InCl3 0020M) assources of S2minus and In3+ respectively acetic acid (Es-Science)(HA) and sodium citrate (Riedel-de Haen) (Cit 0035M)were used as complexing agents of In3+ The entire reactioncan be written as follows

[In (Ac)4minus119909HCit119909](ac) + CH3SCNH2(ac) +H3O+(ac)

997888rarr In2S3(s) + 119909HCit(ac) + (4 minus 119909)HAc(ac)

+ NCNH2(ac) +H2O (2)

(1)

All reagents were mixed in pH at 25 and temperatureat 70∘C after that substrate (soda lime glass) was immersedinto reaction reactor and time reaction begins After reactionfinished solution of reaction was filtered for using filterpaper powder-In2S3 was cleaned with bidistilled water afterthat compound was dried on a hot plate at 40∘C by 1 hourAfter this process we obtained dry powder-In2S3

22 Compound Characterization The optical properties ofcompoundwere studied through diffuse reflectancemeasure-ments study was carried out in a Lambda 4 Perkin Elmerspectrophotometer equipped with an integrating sphere

Kubelka-Munk model and analysis based on differentialreflection spectra were used to determine independently theenergies of the fundamental optical transitions X-ray diffrac-tion patterns of the samples were recorded in Shimadzu6000 diffractometer with a source of Cu-K120572 radiation (120582 =015418 nm) in a range diffraction angle 2120579 between 20∘ and80∘ The Raman spectra were measured in a backscatteringconfiguration at room temperature the excitation radiationwavelength was 780 nm the Raman peak analysis is based onLorentzian-fitting performed in the range of 100ndash500 cmminus1

23 Adsorption Study All reagents used in this work were ofanalytical gradeTheMBwas supplied by Sigma-Aldrich CASNumber 7220-79-3 We provided 4 different concentrationsrsquoMB on 0025 g of In2S3 Powder was immersed in eachsolution and systemwasmagnetically stirred in the dark untilreaching the equilibrium of dye adsorptionndashdesorption onIn2S3 surface the concentration of MB dye was determinedby spectrophotometry (HR2000CGUV-NIR ocean optics) at120582 = 665 nm Content dye of the each solution was determinedeach five (5) minutes by spectrophotometry prior to theconcentration measurement samples were filtered through045mm membrane all adsorption processes were carriedout at 298K

24 Photocatalytic Activity In photocatalytic process weused a batch photoreactor under visible irradiation 100WOSRAM halogen immersion lamp 0025 g of In2S3 wasimmersed in the reactor with solution MB (10 ppm) duringthe photodegradation process air was injected to reactorthe illumination time was beginning after 60 minutes ofdark stirring to reach adsorption equilibrium finally theconcentration of dye was determined by spectrophotometryat 120582 = 665 nm

3 Results and Discussions

31 Structural Study Hydrodynamic synthesis conditions inCBD process (eg pH ion concentration and temperature)determine both the phase and preferential growth planes ofcrystalline structure of solid deposited [18] Figure 1 showsXRD diffraction pattern of powder synthesized by CBDprocess preferential growth planes are shown inside figureXRD pattern shows powder is polycrystalline besides mainreflections can be assigned to cubic structure of In2S3 (JCPDSnumber 65-0459) it has 4 the preferential growth planes (311)(222) (400) and (440) this result is according to othersreposts this crystalline phase has reported photocatalyticactivity for water splitting under visible radiation [19]

32 Optical Study The optical properties of catalyst weredetermined from diffuse reflectance measurements in therange of 400ndash900 nmUV-Vis diffuse reflectance spectrawereanalyzed with Kubelka-Munk remission function given bythe equation below [20]

119865 (119877120572) =(1 minus 119877120572)

2

2119877120572 (2)

Advances in Physical Chemistry 3Re

flect

ion

(au

)

400 450 500 550 600 650 700 750 800 850 900

Wavelength (nm)

2 22 24 26 28 3

(F(R

)lowastℎ

ℎ (eV)

)2

Figure 2 Reflectance diffuse spectra of In2S3 powder (Kubelka-Munk fitting as function of photon energy)

where 119877120572 is the reflectance and 119865(119877120572) is proportional tothe absorption constant of the material an indicative ofthe absorbance of the sample at a particular wavelengthFor using Kubelka-Munk function (2) on the reflectancespectrum we can obtain the graph of absorbance versuswavelength Figure 2 shows the Kubelka-Munk functionversus photon energy The optical band gap of the films wasdetermined by extrapolating the linear portion of (119865(119877120572)ℎV)2versus ℎV plot on the 119909-axis

(119865 (119877120572) ℎV)2 = 119860 (ℎV minus 119864119892) (3)

where ldquo119864119892rdquo is the band gap energy and ldquo119860rdquo is a constantdepending on the transition probability

Figure 2 (insight) shows that the band gap of thecompound was 247 eV All signals of diffraction patterncorrespond to In2S3 however this value is higher than thevalue reported to bulk In2S3 value of 207 eV in CBD processprecipitation of other phases (eg oxides and hydroxides)had been reported if they are present in the catalyst theycan increase the band gap value Furthermore band gap valueindicates that catalyst can be active in the visible region of theelectromagnetic spectrum if semiconductor absorbs visibleradiation it could be useful for degrading pollutant for usingdirect solar radiation [21 22]

33 Raman Spectroscopy Study Figure 3 shows modesobtained by Raman spectra for catalyst powder definitionand intensity of the signal in Raman spectra revealed highcrystalline quality of catalyst this result is according to XRDpattern diffraction Raman spectra show five normal modesof vibration at 155 cmminus1 186 cmminus1 218 cmminus1 243 cmminus1 and305 cmminus1 these signals can be assigned tomodes of vibrationsof In2S3 phase signals located at 186 cmminus1 243 cmminus1 and305 cmminus1 can be assigned to A1g vibration modes of In2S3phase this result is according to other reports [23]

34 Adsorption Process In relation to photocatalytic degra-dation step of physical or chemical adsorption process prior

lowast

lowast

lowast

lowast

lowast lowast

100 150 200 250 300 350 400

Inte

nsity

(au

)

Raman shift (cmminus1)

In2S3

Figure 3 Raman spectra of In2S3 powder

to beginning of photodegradation step is a process poorlystudied it is well known that the adsorption of contaminantspecies on the surface of the photocatalyst is an importantstep prior to degradation process In this study Langmuir andFreundlich isotherm models were employed to describe theMB adsorption equilibrium In Langmuir isotherm modelthe adsorption process is taking place isothermally andadsorbent surface can be covered uniformlywith amonolayerof adsorbate The linear form of the Langmuir equation is

119862119890119902= 1119902119898119887+ 119862119890119902119898 (4)

where 119862119890 is the equilibrium concentration of dye 119902 is theamount of dye adsorbed per gram of catalyst 119902119898 representsthe maximum amount of dye that can be adsorbed and119887 is related to the adsorption rate The linear form of theFreundlich equation is

ln (119902) = ln (119896) + 1119899ln119862eq (5)

where 119896 is an indicator of adsorption capacity as the higherthe maximum capacity is the higher the 119896 value is further-more ratio (1119899) is a measure of intensity adsorption The 119899and 119896 values are empirical constants and they are specific tothe system adsorbentadsorbate [24]

Figure 4 shows the experimental results of adsorptionequilibrium of different loads of MB on 025 g of In2S3powder

Figure 4 shows adsorption kinetics of MB over In2S3results show that system reaches adsorption equilibriumpoint after 1 hour of dark agitation from experimental resultsof Figure 4 and applying fitting of (4) and (5) we obtainadsorption isotherms for two theoretical models Table 1 liststhe fitting results and Figure 5 shows the experimental resultsof adsorption equilibrium of MB on In2S3 and theoretical fit-ting to Langmuir model The fitting results indicated that theLangmuir isotherm describes the experimental results MBadsorption equilibrium

35 Photocatalytic Test Figure 6 shows change of molarfraction (119909) of MB under both dark and visible irradiation

4 Advances in Physical Chemistry

0 20 40 60 80 100

Time (min)

CeC

o

50 ppm MB30 ppm MB

20 ppm MB10 ppm MB

0

0102030405060708091

Figure 4 Adsorption process of In2S3 powder (0025 g) at differentMB loads

0 10 20 30 40

ExperimentalLangmuir

0

5

10

15

20

25

30

q (m

gg)

Ce (mgL)

Figure 5 Langmuir and Freundlichmodel fitting toMB adsorptionon In2S3 powder

Table 1 Linear fitting experimental results

Model Parameter(unit) Value

Langmuir119876119898 (mgg)119870 (Lg)1198772

253070979

Freundlich1198991198961198772

58320627

In2S3 adsorption on dark stirring occurs until 60 minutesafter that visible irradiation begins and significant increasein photocatalytic activity was observed Adsorption and

Time (min)

Time (min)

CtC

o

60

70 80 90

100

110

120

130

ln(C

tC

o)

0

01

02

03

04

05

06

07

08

09

1

minus21minus19minus17minus15minus13minus11minus09minus07minus05

Adsorption process Irradiation Photocatalytic process

0 20 40 60 80 100 120 140

Figure 6 MB removal yield in dark stirring and under visible lightirradiation

photomineralization rate of methylene blue followed theLangmuirndashHinshelwood (L-H) kinetics model [25]

V = minus119889 [MB]119889119905= minus 119896119870 [MB]1 + 119870 [MB]

(6)

where V is the rate of dyemineralization 119896 is the rate constant[MB] is the methylene blue concentration and 119870 is theadsorption coefficient Equation (6) can be solved explicitlyfor (119905) for using discrete changes in [MB] from the initialconcentration to a zero reference point In our case anapparent first-order model can be assumed

V = minus119889 [MB]119889119905= 1198961015840 [MB] = 119896119870 [MB] (7)

Integration result in ((6) and (7)) is as follows

[MB] = [MB]119900 119890minus1198961015840119905 (8)

where (119905) is time in minutes and 1198961015840 is the apparent reactionrate constant (minminus1) the assumption of a pseudo-first-ordermodel was used in several studies to characterize the effectof different experimental conditions on the degradation rate[26]

Figure 6 shows change of methylene blue removal yieldboth in dark stirring and under visible light illuminationinside we show pseudo-first-order model fitting Figure 6shows after 60 minutes a plateau zone is reached under darkstirring after that under visible irradiation system reaches86 of MB concentration reduction this 26 could beassigned to photocatalytic processThese results indicate thatIn2S3 has photocatalytic properties under visible irradiationThe 1198961015840 value for In2S3 was established from the slope of thelinear fitting of ln(MBMB119900) versus time We obtained a 1198961015840value of 24 times 10minus2minminus1 This is a significant result due topossibility of using visible radiation directly under catalystswithout physical or chemical modification as TiO2 requiredto be photocatalytically active under visible irradiation

Advances in Physical Chemistry 5

4 Conclusions

We synthesized In2S3 by CBD process Structural character-ization indicated that catalyst powder was polycrystallinebesides optical analysis indicated that compound was activein visible region of electromagnetic spectrum it had a bandgap of 247 eV Furthermore Langmuir adsorption modeldescribed equilibrium adsorption of MB on In2S3 FinallyIn2S3 had photocatalytic activity on MB degradation resultsindicated that MB load reduced 26 after visible illumina-tion

Conflicts of Interest

The authors declare that they have no conflicts of interest

Acknowledgments

This research was supported by Universidad del Atlantico(Project Code CB20-FGI2016)

References

[1] M Mehrjouei S Muller and D Moller ldquoA review on photo-catalytic ozonation used for the treatment of water and wastew-aterrdquo Chemical Engineering Journal vol 263 pp 209ndash219 2015

[2] M Juntti D Russel and J Turnpenny ldquoEvidence politics andpower in public policy for the environmentrdquo EnvironmentalScience and Policy vol 12 no 3 pp 207ndash215 2009

[3] K AnnanWater for People Water for Life Executive Summaryof the UNWorld Development Report UNESCO-WWAP 2003

[4] A Ahmadi and L Tiruta-Barna ldquoA process modelling-life cycleassessment-multiobjective optimization tool for the eco-designof conventional treatment processes of potable waterrdquo Journalof Cleaner Production vol 100 pp 116ndash125 2015

[5] C V Gomez-Pacheco J Rivera-Utrilla M Sanchez-Polo and JJ Lopez-Penalver ldquoOptimization of the preparation process ofbiological sludge adsorbents for application inwater treatmentrdquoJournal of Hazardous Materials vol 217-218 pp 76ndash84 2012

[6] P Wang N Xu and J Shi ldquoA pilot study of the treatment ofwaste rolling emulsion using zirconia microfiltration mem-branesrdquo Journal ofMembrane Science vol 173 no 2 pp 159ndash1662000

[7] R Tarpagkou and A Pantokratoras ldquoThe influence of lamellarsettler in sedimentation tanks for potable water treatmentmdashacomputational fluid dynamic studyrdquo Powder Technology vol268 no 1 pp 139ndash149 2014

[8] E Repo M Makinen S Rengaraj G Natarajan A Bhatnagarand M Sillanpaa ldquoLepidocrocite and its heat-treated formsas effective arsenic adsorbents in aqueous mediumrdquo ChemicalEngineering Journal vol 180 pp 159ndash169 2012

[9] D Li Q Zhu C Han Y Yang W Jiang and Z Zhang ldquoPhoto-catalytic degradation of recalcitrant organic pollutants in waterusing a novel cylindrical multi-column photoreactor packedwith TiO2-coated silica gel beadsrdquo Journal of Hazardous Mate-rials vol 285 pp 398ndash408 2015

[10] B AWols andCHMHofman-Caris ldquoReview of photochem-ical reaction constants of organic micropollutants required forUVadvanced oxidation processes inwaterrdquoWater Research vol46 no 9 pp 2815ndash2827 2012

[11] Z Wang X Liu W Li H Wang and H Li ldquoEnhancing thephotocatalytic degradation of salicylic acid by using molecularimprinted S-doped TiO2 under simulated solar lightrdquo CeramicsInternational vol 40 no 6 pp 8863ndash8867 2014

[12] M V Dozzi and E Selli ldquoDoping TiO2 with p-block elementseffects on photocatalytic activityrdquo Journal of Photochemistry andPhotobiology C Photochemistry Reviews vol 14 no 1 pp 13ndash282013

[13] G R Gopinatha R W Milesb and K T R Reddya ldquoInfluenceof bath temperature on the properties of In2S3 films grown bychemical bath depositionrdquo Energy Procedia vol 34 pp 399ndash406 2013

[14] W Wang G Huang J C Yu and P K Wong ldquoAdvances inphotocatalytic disinfection of bacteria development of photo-catalysts and mechanismsrdquo Journal of Environmental Sciencesvol 34 pp 232ndash247 2015

[15] T Sall B M Soucase M Mollar B Hartitti and M FahoumeldquoChemical spray pyrolysis of 120573-In2S3 thin films deposited atdifferent temperaturesrdquo Journal of Physics and Chemistry ofSolids vol 76 pp 100ndash104 2015

[16] R Lucena F Fresno and J C Conesa ldquoSpectral response andstability of In2S3 as visible light-active photocatalystrdquo CatalysisCommunications vol 20 pp 1ndash5 2012

[17] J Chen W Liu and W Gao ldquoTuning photocatalytic activityof In2S3 broadband spectrum photocatalyst based on morphol-ogyrdquo Applied Surface Science vol 368 pp 288ndash297 2016

[18] R Bayon and J Herrero ldquoStructure and morphology of theindium hydroxy sulphide thin filmsrdquo Applied Surface Sciencevol 158 no 1 pp 49ndash57 2000

[19] N Revathi P Prathap and K T R Reddy ldquoSynthesis andphysical behaviour of In2S3 filmsrdquo Applied Surface Science vol254 no 16 pp 5291ndash5298 2008

[20] M Burgos andM Langlet ldquoThe sol-gel transformation of TIPTcoatings a FTIR studyrdquo Thin Solid Films vol 349 no 1-2 pp19ndash23 1999

[21] P Roy J R Ota and S K Srivastava ldquoCrystalline ZnS thin filmsby chemical bath deposition method and its characterizationrdquoThin Solid Films vol 515 no 4 pp 1912ndash1917 2006

[22] N Naghavi R Henriquez V Laptev and D Lincot ldquoGrowthstudies and characterisation of In2S3 thin films deposited byatomic layer deposition (ALD)rdquo Applied Surface Science vol222 no 1ndash4 pp 65ndash73 2004

[23] E Karber K Otto A Katerski A Mere and M KrunksldquoRaman spectroscopic study of In2S3 films prepared by spraypyrolysisrdquo Materials Science in Semiconductor Processing vol25 pp 137ndash142 2014

[24] J E House Principles of Chemical Kinetics Elsevier Press 2007[25] P Simoncic and T Armbruster ldquoCationic methylene blue

incorporated into zeolite mordenite-Na a single crystal X-raystudyrdquo Microporous and Mesoporous Materials vol 81 no 1ndash3pp 87ndash95 2005

[26] T Zhang T Oyama A Aoshima H Hidaka J Zhao and NSerpone ldquoPhotooxidative N-demethylation of methylene bluein aqueous TiO2 dispersions under UV irradiationrdquo Journal ofPhotochemistry and Photobiology A Chemistry vol 140 no 2pp 163ndash172 2001

Submit your manuscripts athttpswwwhindawicom

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International Journal ofInternational Journal of

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Advances in

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Medicinal ChemistryInternational Journal of

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CatalystsJournal of

Page 2: Methylene Blue Photocatalytic Degradation under Visible ...downloads.hindawi.com/archive/2017/6358601.pdf · ResearchArticle Methylene Blue Photocatalytic Degradation under Visible

2 Advances in Physical Chemistry

0

20

40

60

80

100

120

140

20 30 40 50 60 70

2휃 (degree)

(au

)

(311

)

In2S3 (JCPDS number 65-0459)

(222

)

(400

)

(511

)

(440

)

(533

)

(444

)Figure 1 XRDpattern of In2S3 powder synthesized byCBDprocess

Thesemethodologies improve photoactivity of TiO2 at visibleregion of electromagnetic spectrum [12] Another alternativeincludes change of TiO2 for other semiconductor havinglower band gap value and potential photocatalytic activityIn2S3 is considered a promising material due to its chemicalstability and its activity in visible range of the electromagneticspectrum it has three different crystalline structures andit has potential photocatalytic activity [13ndash15] It has beenreported that this compound exhibits photocatalytic activityin the degradation of aqueous formic acid andmethyl orangeunder visible light irradiation [16 17]

The aim of this study is to evaluate the photocatalyticactivity of In2S3 synthesized by CBD in the degradation ofmethylene blue as a potential alternative in photocatalysis

2 Experimental

21 Compound Synthesis Powder of In2S3 was synthesized byCBDprocess from solution containing thioacetamide (Schar-lau) (TA 0350M) and indium chloride (InCl3 0020M) assources of S2minus and In3+ respectively acetic acid (Es-Science)(HA) and sodium citrate (Riedel-de Haen) (Cit 0035M)were used as complexing agents of In3+ The entire reactioncan be written as follows

[In (Ac)4minus119909HCit119909](ac) + CH3SCNH2(ac) +H3O+(ac)

997888rarr In2S3(s) + 119909HCit(ac) + (4 minus 119909)HAc(ac)

+ NCNH2(ac) +H2O (2)

(1)

All reagents were mixed in pH at 25 and temperatureat 70∘C after that substrate (soda lime glass) was immersedinto reaction reactor and time reaction begins After reactionfinished solution of reaction was filtered for using filterpaper powder-In2S3 was cleaned with bidistilled water afterthat compound was dried on a hot plate at 40∘C by 1 hourAfter this process we obtained dry powder-In2S3

22 Compound Characterization The optical properties ofcompoundwere studied through diffuse reflectancemeasure-ments study was carried out in a Lambda 4 Perkin Elmerspectrophotometer equipped with an integrating sphere

Kubelka-Munk model and analysis based on differentialreflection spectra were used to determine independently theenergies of the fundamental optical transitions X-ray diffrac-tion patterns of the samples were recorded in Shimadzu6000 diffractometer with a source of Cu-K120572 radiation (120582 =015418 nm) in a range diffraction angle 2120579 between 20∘ and80∘ The Raman spectra were measured in a backscatteringconfiguration at room temperature the excitation radiationwavelength was 780 nm the Raman peak analysis is based onLorentzian-fitting performed in the range of 100ndash500 cmminus1

23 Adsorption Study All reagents used in this work were ofanalytical gradeTheMBwas supplied by Sigma-Aldrich CASNumber 7220-79-3 We provided 4 different concentrationsrsquoMB on 0025 g of In2S3 Powder was immersed in eachsolution and systemwasmagnetically stirred in the dark untilreaching the equilibrium of dye adsorptionndashdesorption onIn2S3 surface the concentration of MB dye was determinedby spectrophotometry (HR2000CGUV-NIR ocean optics) at120582 = 665 nm Content dye of the each solution was determinedeach five (5) minutes by spectrophotometry prior to theconcentration measurement samples were filtered through045mm membrane all adsorption processes were carriedout at 298K

24 Photocatalytic Activity In photocatalytic process weused a batch photoreactor under visible irradiation 100WOSRAM halogen immersion lamp 0025 g of In2S3 wasimmersed in the reactor with solution MB (10 ppm) duringthe photodegradation process air was injected to reactorthe illumination time was beginning after 60 minutes ofdark stirring to reach adsorption equilibrium finally theconcentration of dye was determined by spectrophotometryat 120582 = 665 nm

3 Results and Discussions

31 Structural Study Hydrodynamic synthesis conditions inCBD process (eg pH ion concentration and temperature)determine both the phase and preferential growth planes ofcrystalline structure of solid deposited [18] Figure 1 showsXRD diffraction pattern of powder synthesized by CBDprocess preferential growth planes are shown inside figureXRD pattern shows powder is polycrystalline besides mainreflections can be assigned to cubic structure of In2S3 (JCPDSnumber 65-0459) it has 4 the preferential growth planes (311)(222) (400) and (440) this result is according to othersreposts this crystalline phase has reported photocatalyticactivity for water splitting under visible radiation [19]

32 Optical Study The optical properties of catalyst weredetermined from diffuse reflectance measurements in therange of 400ndash900 nmUV-Vis diffuse reflectance spectrawereanalyzed with Kubelka-Munk remission function given bythe equation below [20]

119865 (119877120572) =(1 minus 119877120572)

2

2119877120572 (2)

Advances in Physical Chemistry 3Re

flect

ion

(au

)

400 450 500 550 600 650 700 750 800 850 900

Wavelength (nm)

2 22 24 26 28 3

(F(R

)lowastℎ

ℎ (eV)

)2

Figure 2 Reflectance diffuse spectra of In2S3 powder (Kubelka-Munk fitting as function of photon energy)

where 119877120572 is the reflectance and 119865(119877120572) is proportional tothe absorption constant of the material an indicative ofthe absorbance of the sample at a particular wavelengthFor using Kubelka-Munk function (2) on the reflectancespectrum we can obtain the graph of absorbance versuswavelength Figure 2 shows the Kubelka-Munk functionversus photon energy The optical band gap of the films wasdetermined by extrapolating the linear portion of (119865(119877120572)ℎV)2versus ℎV plot on the 119909-axis

(119865 (119877120572) ℎV)2 = 119860 (ℎV minus 119864119892) (3)

where ldquo119864119892rdquo is the band gap energy and ldquo119860rdquo is a constantdepending on the transition probability

Figure 2 (insight) shows that the band gap of thecompound was 247 eV All signals of diffraction patterncorrespond to In2S3 however this value is higher than thevalue reported to bulk In2S3 value of 207 eV in CBD processprecipitation of other phases (eg oxides and hydroxides)had been reported if they are present in the catalyst theycan increase the band gap value Furthermore band gap valueindicates that catalyst can be active in the visible region of theelectromagnetic spectrum if semiconductor absorbs visibleradiation it could be useful for degrading pollutant for usingdirect solar radiation [21 22]

33 Raman Spectroscopy Study Figure 3 shows modesobtained by Raman spectra for catalyst powder definitionand intensity of the signal in Raman spectra revealed highcrystalline quality of catalyst this result is according to XRDpattern diffraction Raman spectra show five normal modesof vibration at 155 cmminus1 186 cmminus1 218 cmminus1 243 cmminus1 and305 cmminus1 these signals can be assigned tomodes of vibrationsof In2S3 phase signals located at 186 cmminus1 243 cmminus1 and305 cmminus1 can be assigned to A1g vibration modes of In2S3phase this result is according to other reports [23]

34 Adsorption Process In relation to photocatalytic degra-dation step of physical or chemical adsorption process prior

lowast

lowast

lowast

lowast

lowast lowast

100 150 200 250 300 350 400

Inte

nsity

(au

)

Raman shift (cmminus1)

In2S3

Figure 3 Raman spectra of In2S3 powder

to beginning of photodegradation step is a process poorlystudied it is well known that the adsorption of contaminantspecies on the surface of the photocatalyst is an importantstep prior to degradation process In this study Langmuir andFreundlich isotherm models were employed to describe theMB adsorption equilibrium In Langmuir isotherm modelthe adsorption process is taking place isothermally andadsorbent surface can be covered uniformlywith amonolayerof adsorbate The linear form of the Langmuir equation is

119862119890119902= 1119902119898119887+ 119862119890119902119898 (4)

where 119862119890 is the equilibrium concentration of dye 119902 is theamount of dye adsorbed per gram of catalyst 119902119898 representsthe maximum amount of dye that can be adsorbed and119887 is related to the adsorption rate The linear form of theFreundlich equation is

ln (119902) = ln (119896) + 1119899ln119862eq (5)

where 119896 is an indicator of adsorption capacity as the higherthe maximum capacity is the higher the 119896 value is further-more ratio (1119899) is a measure of intensity adsorption The 119899and 119896 values are empirical constants and they are specific tothe system adsorbentadsorbate [24]

Figure 4 shows the experimental results of adsorptionequilibrium of different loads of MB on 025 g of In2S3powder

Figure 4 shows adsorption kinetics of MB over In2S3results show that system reaches adsorption equilibriumpoint after 1 hour of dark agitation from experimental resultsof Figure 4 and applying fitting of (4) and (5) we obtainadsorption isotherms for two theoretical models Table 1 liststhe fitting results and Figure 5 shows the experimental resultsof adsorption equilibrium of MB on In2S3 and theoretical fit-ting to Langmuir model The fitting results indicated that theLangmuir isotherm describes the experimental results MBadsorption equilibrium

35 Photocatalytic Test Figure 6 shows change of molarfraction (119909) of MB under both dark and visible irradiation

4 Advances in Physical Chemistry

0 20 40 60 80 100

Time (min)

CeC

o

50 ppm MB30 ppm MB

20 ppm MB10 ppm MB

0

0102030405060708091

Figure 4 Adsorption process of In2S3 powder (0025 g) at differentMB loads

0 10 20 30 40

ExperimentalLangmuir

0

5

10

15

20

25

30

q (m

gg)

Ce (mgL)

Figure 5 Langmuir and Freundlichmodel fitting toMB adsorptionon In2S3 powder

Table 1 Linear fitting experimental results

Model Parameter(unit) Value

Langmuir119876119898 (mgg)119870 (Lg)1198772

253070979

Freundlich1198991198961198772

58320627

In2S3 adsorption on dark stirring occurs until 60 minutesafter that visible irradiation begins and significant increasein photocatalytic activity was observed Adsorption and

Time (min)

Time (min)

CtC

o

60

70 80 90

100

110

120

130

ln(C

tC

o)

0

01

02

03

04

05

06

07

08

09

1

minus21minus19minus17minus15minus13minus11minus09minus07minus05

Adsorption process Irradiation Photocatalytic process

0 20 40 60 80 100 120 140

Figure 6 MB removal yield in dark stirring and under visible lightirradiation

photomineralization rate of methylene blue followed theLangmuirndashHinshelwood (L-H) kinetics model [25]

V = minus119889 [MB]119889119905= minus 119896119870 [MB]1 + 119870 [MB]

(6)

where V is the rate of dyemineralization 119896 is the rate constant[MB] is the methylene blue concentration and 119870 is theadsorption coefficient Equation (6) can be solved explicitlyfor (119905) for using discrete changes in [MB] from the initialconcentration to a zero reference point In our case anapparent first-order model can be assumed

V = minus119889 [MB]119889119905= 1198961015840 [MB] = 119896119870 [MB] (7)

Integration result in ((6) and (7)) is as follows

[MB] = [MB]119900 119890minus1198961015840119905 (8)

where (119905) is time in minutes and 1198961015840 is the apparent reactionrate constant (minminus1) the assumption of a pseudo-first-ordermodel was used in several studies to characterize the effectof different experimental conditions on the degradation rate[26]

Figure 6 shows change of methylene blue removal yieldboth in dark stirring and under visible light illuminationinside we show pseudo-first-order model fitting Figure 6shows after 60 minutes a plateau zone is reached under darkstirring after that under visible irradiation system reaches86 of MB concentration reduction this 26 could beassigned to photocatalytic processThese results indicate thatIn2S3 has photocatalytic properties under visible irradiationThe 1198961015840 value for In2S3 was established from the slope of thelinear fitting of ln(MBMB119900) versus time We obtained a 1198961015840value of 24 times 10minus2minminus1 This is a significant result due topossibility of using visible radiation directly under catalystswithout physical or chemical modification as TiO2 requiredto be photocatalytically active under visible irradiation

Advances in Physical Chemistry 5

4 Conclusions

We synthesized In2S3 by CBD process Structural character-ization indicated that catalyst powder was polycrystallinebesides optical analysis indicated that compound was activein visible region of electromagnetic spectrum it had a bandgap of 247 eV Furthermore Langmuir adsorption modeldescribed equilibrium adsorption of MB on In2S3 FinallyIn2S3 had photocatalytic activity on MB degradation resultsindicated that MB load reduced 26 after visible illumina-tion

Conflicts of Interest

The authors declare that they have no conflicts of interest

Acknowledgments

This research was supported by Universidad del Atlantico(Project Code CB20-FGI2016)

References

[1] M Mehrjouei S Muller and D Moller ldquoA review on photo-catalytic ozonation used for the treatment of water and wastew-aterrdquo Chemical Engineering Journal vol 263 pp 209ndash219 2015

[2] M Juntti D Russel and J Turnpenny ldquoEvidence politics andpower in public policy for the environmentrdquo EnvironmentalScience and Policy vol 12 no 3 pp 207ndash215 2009

[3] K AnnanWater for People Water for Life Executive Summaryof the UNWorld Development Report UNESCO-WWAP 2003

[4] A Ahmadi and L Tiruta-Barna ldquoA process modelling-life cycleassessment-multiobjective optimization tool for the eco-designof conventional treatment processes of potable waterrdquo Journalof Cleaner Production vol 100 pp 116ndash125 2015

[5] C V Gomez-Pacheco J Rivera-Utrilla M Sanchez-Polo and JJ Lopez-Penalver ldquoOptimization of the preparation process ofbiological sludge adsorbents for application inwater treatmentrdquoJournal of Hazardous Materials vol 217-218 pp 76ndash84 2012

[6] P Wang N Xu and J Shi ldquoA pilot study of the treatment ofwaste rolling emulsion using zirconia microfiltration mem-branesrdquo Journal ofMembrane Science vol 173 no 2 pp 159ndash1662000

[7] R Tarpagkou and A Pantokratoras ldquoThe influence of lamellarsettler in sedimentation tanks for potable water treatmentmdashacomputational fluid dynamic studyrdquo Powder Technology vol268 no 1 pp 139ndash149 2014

[8] E Repo M Makinen S Rengaraj G Natarajan A Bhatnagarand M Sillanpaa ldquoLepidocrocite and its heat-treated formsas effective arsenic adsorbents in aqueous mediumrdquo ChemicalEngineering Journal vol 180 pp 159ndash169 2012

[9] D Li Q Zhu C Han Y Yang W Jiang and Z Zhang ldquoPhoto-catalytic degradation of recalcitrant organic pollutants in waterusing a novel cylindrical multi-column photoreactor packedwith TiO2-coated silica gel beadsrdquo Journal of Hazardous Mate-rials vol 285 pp 398ndash408 2015

[10] B AWols andCHMHofman-Caris ldquoReview of photochem-ical reaction constants of organic micropollutants required forUVadvanced oxidation processes inwaterrdquoWater Research vol46 no 9 pp 2815ndash2827 2012

[11] Z Wang X Liu W Li H Wang and H Li ldquoEnhancing thephotocatalytic degradation of salicylic acid by using molecularimprinted S-doped TiO2 under simulated solar lightrdquo CeramicsInternational vol 40 no 6 pp 8863ndash8867 2014

[12] M V Dozzi and E Selli ldquoDoping TiO2 with p-block elementseffects on photocatalytic activityrdquo Journal of Photochemistry andPhotobiology C Photochemistry Reviews vol 14 no 1 pp 13ndash282013

[13] G R Gopinatha R W Milesb and K T R Reddya ldquoInfluenceof bath temperature on the properties of In2S3 films grown bychemical bath depositionrdquo Energy Procedia vol 34 pp 399ndash406 2013

[14] W Wang G Huang J C Yu and P K Wong ldquoAdvances inphotocatalytic disinfection of bacteria development of photo-catalysts and mechanismsrdquo Journal of Environmental Sciencesvol 34 pp 232ndash247 2015

[15] T Sall B M Soucase M Mollar B Hartitti and M FahoumeldquoChemical spray pyrolysis of 120573-In2S3 thin films deposited atdifferent temperaturesrdquo Journal of Physics and Chemistry ofSolids vol 76 pp 100ndash104 2015

[16] R Lucena F Fresno and J C Conesa ldquoSpectral response andstability of In2S3 as visible light-active photocatalystrdquo CatalysisCommunications vol 20 pp 1ndash5 2012

[17] J Chen W Liu and W Gao ldquoTuning photocatalytic activityof In2S3 broadband spectrum photocatalyst based on morphol-ogyrdquo Applied Surface Science vol 368 pp 288ndash297 2016

[18] R Bayon and J Herrero ldquoStructure and morphology of theindium hydroxy sulphide thin filmsrdquo Applied Surface Sciencevol 158 no 1 pp 49ndash57 2000

[19] N Revathi P Prathap and K T R Reddy ldquoSynthesis andphysical behaviour of In2S3 filmsrdquo Applied Surface Science vol254 no 16 pp 5291ndash5298 2008

[20] M Burgos andM Langlet ldquoThe sol-gel transformation of TIPTcoatings a FTIR studyrdquo Thin Solid Films vol 349 no 1-2 pp19ndash23 1999

[21] P Roy J R Ota and S K Srivastava ldquoCrystalline ZnS thin filmsby chemical bath deposition method and its characterizationrdquoThin Solid Films vol 515 no 4 pp 1912ndash1917 2006

[22] N Naghavi R Henriquez V Laptev and D Lincot ldquoGrowthstudies and characterisation of In2S3 thin films deposited byatomic layer deposition (ALD)rdquo Applied Surface Science vol222 no 1ndash4 pp 65ndash73 2004

[23] E Karber K Otto A Katerski A Mere and M KrunksldquoRaman spectroscopic study of In2S3 films prepared by spraypyrolysisrdquo Materials Science in Semiconductor Processing vol25 pp 137ndash142 2014

[24] J E House Principles of Chemical Kinetics Elsevier Press 2007[25] P Simoncic and T Armbruster ldquoCationic methylene blue

incorporated into zeolite mordenite-Na a single crystal X-raystudyrdquo Microporous and Mesoporous Materials vol 81 no 1ndash3pp 87ndash95 2005

[26] T Zhang T Oyama A Aoshima H Hidaka J Zhao and NSerpone ldquoPhotooxidative N-demethylation of methylene bluein aqueous TiO2 dispersions under UV irradiationrdquo Journal ofPhotochemistry and Photobiology A Chemistry vol 140 no 2pp 163ndash172 2001

Submit your manuscripts athttpswwwhindawicom

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Inorganic ChemistryInternational Journal of

Hindawi Publishing Corporation httpwwwhindawicom Volume 201

International Journal ofInternational Journal ofPhotoenergy

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Carbohydrate Chemistry

International Journal ofInternational Journal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Journal of

Chemistry

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Advances in

Physical Chemistry

Hindawi Publishing Corporationhttpwwwhindawicom

Analytical Methods in Chemistry

Journal of

Volume 2014

Bioinorganic Chemistry and ApplicationsHindawi Publishing Corporationhttpwwwhindawicom Volume 2014

SpectroscopyInternational Journal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

The Scientific World JournalHindawi Publishing Corporation httpwwwhindawicom Volume 2014

Medicinal ChemistryInternational Journal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Chromatography Research International

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Applied ChemistryJournal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Theoretical ChemistryJournal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Journal of

Spectroscopy

Analytical ChemistryInternational Journal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Journal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Quantum Chemistry

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Organic Chemistry International

ElectrochemistryInternational Journal of

Hindawi Publishing Corporation httpwwwhindawicom Volume 2014

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

CatalystsJournal of

Page 3: Methylene Blue Photocatalytic Degradation under Visible ...downloads.hindawi.com/archive/2017/6358601.pdf · ResearchArticle Methylene Blue Photocatalytic Degradation under Visible

Advances in Physical Chemistry 3Re

flect

ion

(au

)

400 450 500 550 600 650 700 750 800 850 900

Wavelength (nm)

2 22 24 26 28 3

(F(R

)lowastℎ

ℎ (eV)

)2

Figure 2 Reflectance diffuse spectra of In2S3 powder (Kubelka-Munk fitting as function of photon energy)

where 119877120572 is the reflectance and 119865(119877120572) is proportional tothe absorption constant of the material an indicative ofthe absorbance of the sample at a particular wavelengthFor using Kubelka-Munk function (2) on the reflectancespectrum we can obtain the graph of absorbance versuswavelength Figure 2 shows the Kubelka-Munk functionversus photon energy The optical band gap of the films wasdetermined by extrapolating the linear portion of (119865(119877120572)ℎV)2versus ℎV plot on the 119909-axis

(119865 (119877120572) ℎV)2 = 119860 (ℎV minus 119864119892) (3)

where ldquo119864119892rdquo is the band gap energy and ldquo119860rdquo is a constantdepending on the transition probability

Figure 2 (insight) shows that the band gap of thecompound was 247 eV All signals of diffraction patterncorrespond to In2S3 however this value is higher than thevalue reported to bulk In2S3 value of 207 eV in CBD processprecipitation of other phases (eg oxides and hydroxides)had been reported if they are present in the catalyst theycan increase the band gap value Furthermore band gap valueindicates that catalyst can be active in the visible region of theelectromagnetic spectrum if semiconductor absorbs visibleradiation it could be useful for degrading pollutant for usingdirect solar radiation [21 22]

33 Raman Spectroscopy Study Figure 3 shows modesobtained by Raman spectra for catalyst powder definitionand intensity of the signal in Raman spectra revealed highcrystalline quality of catalyst this result is according to XRDpattern diffraction Raman spectra show five normal modesof vibration at 155 cmminus1 186 cmminus1 218 cmminus1 243 cmminus1 and305 cmminus1 these signals can be assigned tomodes of vibrationsof In2S3 phase signals located at 186 cmminus1 243 cmminus1 and305 cmminus1 can be assigned to A1g vibration modes of In2S3phase this result is according to other reports [23]

34 Adsorption Process In relation to photocatalytic degra-dation step of physical or chemical adsorption process prior

lowast

lowast

lowast

lowast

lowast lowast

100 150 200 250 300 350 400

Inte

nsity

(au

)

Raman shift (cmminus1)

In2S3

Figure 3 Raman spectra of In2S3 powder

to beginning of photodegradation step is a process poorlystudied it is well known that the adsorption of contaminantspecies on the surface of the photocatalyst is an importantstep prior to degradation process In this study Langmuir andFreundlich isotherm models were employed to describe theMB adsorption equilibrium In Langmuir isotherm modelthe adsorption process is taking place isothermally andadsorbent surface can be covered uniformlywith amonolayerof adsorbate The linear form of the Langmuir equation is

119862119890119902= 1119902119898119887+ 119862119890119902119898 (4)

where 119862119890 is the equilibrium concentration of dye 119902 is theamount of dye adsorbed per gram of catalyst 119902119898 representsthe maximum amount of dye that can be adsorbed and119887 is related to the adsorption rate The linear form of theFreundlich equation is

ln (119902) = ln (119896) + 1119899ln119862eq (5)

where 119896 is an indicator of adsorption capacity as the higherthe maximum capacity is the higher the 119896 value is further-more ratio (1119899) is a measure of intensity adsorption The 119899and 119896 values are empirical constants and they are specific tothe system adsorbentadsorbate [24]

Figure 4 shows the experimental results of adsorptionequilibrium of different loads of MB on 025 g of In2S3powder

Figure 4 shows adsorption kinetics of MB over In2S3results show that system reaches adsorption equilibriumpoint after 1 hour of dark agitation from experimental resultsof Figure 4 and applying fitting of (4) and (5) we obtainadsorption isotherms for two theoretical models Table 1 liststhe fitting results and Figure 5 shows the experimental resultsof adsorption equilibrium of MB on In2S3 and theoretical fit-ting to Langmuir model The fitting results indicated that theLangmuir isotherm describes the experimental results MBadsorption equilibrium

35 Photocatalytic Test Figure 6 shows change of molarfraction (119909) of MB under both dark and visible irradiation

4 Advances in Physical Chemistry

0 20 40 60 80 100

Time (min)

CeC

o

50 ppm MB30 ppm MB

20 ppm MB10 ppm MB

0

0102030405060708091

Figure 4 Adsorption process of In2S3 powder (0025 g) at differentMB loads

0 10 20 30 40

ExperimentalLangmuir

0

5

10

15

20

25

30

q (m

gg)

Ce (mgL)

Figure 5 Langmuir and Freundlichmodel fitting toMB adsorptionon In2S3 powder

Table 1 Linear fitting experimental results

Model Parameter(unit) Value

Langmuir119876119898 (mgg)119870 (Lg)1198772

253070979

Freundlich1198991198961198772

58320627

In2S3 adsorption on dark stirring occurs until 60 minutesafter that visible irradiation begins and significant increasein photocatalytic activity was observed Adsorption and

Time (min)

Time (min)

CtC

o

60

70 80 90

100

110

120

130

ln(C

tC

o)

0

01

02

03

04

05

06

07

08

09

1

minus21minus19minus17minus15minus13minus11minus09minus07minus05

Adsorption process Irradiation Photocatalytic process

0 20 40 60 80 100 120 140

Figure 6 MB removal yield in dark stirring and under visible lightirradiation

photomineralization rate of methylene blue followed theLangmuirndashHinshelwood (L-H) kinetics model [25]

V = minus119889 [MB]119889119905= minus 119896119870 [MB]1 + 119870 [MB]

(6)

where V is the rate of dyemineralization 119896 is the rate constant[MB] is the methylene blue concentration and 119870 is theadsorption coefficient Equation (6) can be solved explicitlyfor (119905) for using discrete changes in [MB] from the initialconcentration to a zero reference point In our case anapparent first-order model can be assumed

V = minus119889 [MB]119889119905= 1198961015840 [MB] = 119896119870 [MB] (7)

Integration result in ((6) and (7)) is as follows

[MB] = [MB]119900 119890minus1198961015840119905 (8)

where (119905) is time in minutes and 1198961015840 is the apparent reactionrate constant (minminus1) the assumption of a pseudo-first-ordermodel was used in several studies to characterize the effectof different experimental conditions on the degradation rate[26]

Figure 6 shows change of methylene blue removal yieldboth in dark stirring and under visible light illuminationinside we show pseudo-first-order model fitting Figure 6shows after 60 minutes a plateau zone is reached under darkstirring after that under visible irradiation system reaches86 of MB concentration reduction this 26 could beassigned to photocatalytic processThese results indicate thatIn2S3 has photocatalytic properties under visible irradiationThe 1198961015840 value for In2S3 was established from the slope of thelinear fitting of ln(MBMB119900) versus time We obtained a 1198961015840value of 24 times 10minus2minminus1 This is a significant result due topossibility of using visible radiation directly under catalystswithout physical or chemical modification as TiO2 requiredto be photocatalytically active under visible irradiation

Advances in Physical Chemistry 5

4 Conclusions

We synthesized In2S3 by CBD process Structural character-ization indicated that catalyst powder was polycrystallinebesides optical analysis indicated that compound was activein visible region of electromagnetic spectrum it had a bandgap of 247 eV Furthermore Langmuir adsorption modeldescribed equilibrium adsorption of MB on In2S3 FinallyIn2S3 had photocatalytic activity on MB degradation resultsindicated that MB load reduced 26 after visible illumina-tion

Conflicts of Interest

The authors declare that they have no conflicts of interest

Acknowledgments

This research was supported by Universidad del Atlantico(Project Code CB20-FGI2016)

References

[1] M Mehrjouei S Muller and D Moller ldquoA review on photo-catalytic ozonation used for the treatment of water and wastew-aterrdquo Chemical Engineering Journal vol 263 pp 209ndash219 2015

[2] M Juntti D Russel and J Turnpenny ldquoEvidence politics andpower in public policy for the environmentrdquo EnvironmentalScience and Policy vol 12 no 3 pp 207ndash215 2009

[3] K AnnanWater for People Water for Life Executive Summaryof the UNWorld Development Report UNESCO-WWAP 2003

[4] A Ahmadi and L Tiruta-Barna ldquoA process modelling-life cycleassessment-multiobjective optimization tool for the eco-designof conventional treatment processes of potable waterrdquo Journalof Cleaner Production vol 100 pp 116ndash125 2015

[5] C V Gomez-Pacheco J Rivera-Utrilla M Sanchez-Polo and JJ Lopez-Penalver ldquoOptimization of the preparation process ofbiological sludge adsorbents for application inwater treatmentrdquoJournal of Hazardous Materials vol 217-218 pp 76ndash84 2012

[6] P Wang N Xu and J Shi ldquoA pilot study of the treatment ofwaste rolling emulsion using zirconia microfiltration mem-branesrdquo Journal ofMembrane Science vol 173 no 2 pp 159ndash1662000

[7] R Tarpagkou and A Pantokratoras ldquoThe influence of lamellarsettler in sedimentation tanks for potable water treatmentmdashacomputational fluid dynamic studyrdquo Powder Technology vol268 no 1 pp 139ndash149 2014

[8] E Repo M Makinen S Rengaraj G Natarajan A Bhatnagarand M Sillanpaa ldquoLepidocrocite and its heat-treated formsas effective arsenic adsorbents in aqueous mediumrdquo ChemicalEngineering Journal vol 180 pp 159ndash169 2012

[9] D Li Q Zhu C Han Y Yang W Jiang and Z Zhang ldquoPhoto-catalytic degradation of recalcitrant organic pollutants in waterusing a novel cylindrical multi-column photoreactor packedwith TiO2-coated silica gel beadsrdquo Journal of Hazardous Mate-rials vol 285 pp 398ndash408 2015

[10] B AWols andCHMHofman-Caris ldquoReview of photochem-ical reaction constants of organic micropollutants required forUVadvanced oxidation processes inwaterrdquoWater Research vol46 no 9 pp 2815ndash2827 2012

[11] Z Wang X Liu W Li H Wang and H Li ldquoEnhancing thephotocatalytic degradation of salicylic acid by using molecularimprinted S-doped TiO2 under simulated solar lightrdquo CeramicsInternational vol 40 no 6 pp 8863ndash8867 2014

[12] M V Dozzi and E Selli ldquoDoping TiO2 with p-block elementseffects on photocatalytic activityrdquo Journal of Photochemistry andPhotobiology C Photochemistry Reviews vol 14 no 1 pp 13ndash282013

[13] G R Gopinatha R W Milesb and K T R Reddya ldquoInfluenceof bath temperature on the properties of In2S3 films grown bychemical bath depositionrdquo Energy Procedia vol 34 pp 399ndash406 2013

[14] W Wang G Huang J C Yu and P K Wong ldquoAdvances inphotocatalytic disinfection of bacteria development of photo-catalysts and mechanismsrdquo Journal of Environmental Sciencesvol 34 pp 232ndash247 2015

[15] T Sall B M Soucase M Mollar B Hartitti and M FahoumeldquoChemical spray pyrolysis of 120573-In2S3 thin films deposited atdifferent temperaturesrdquo Journal of Physics and Chemistry ofSolids vol 76 pp 100ndash104 2015

[16] R Lucena F Fresno and J C Conesa ldquoSpectral response andstability of In2S3 as visible light-active photocatalystrdquo CatalysisCommunications vol 20 pp 1ndash5 2012

[17] J Chen W Liu and W Gao ldquoTuning photocatalytic activityof In2S3 broadband spectrum photocatalyst based on morphol-ogyrdquo Applied Surface Science vol 368 pp 288ndash297 2016

[18] R Bayon and J Herrero ldquoStructure and morphology of theindium hydroxy sulphide thin filmsrdquo Applied Surface Sciencevol 158 no 1 pp 49ndash57 2000

[19] N Revathi P Prathap and K T R Reddy ldquoSynthesis andphysical behaviour of In2S3 filmsrdquo Applied Surface Science vol254 no 16 pp 5291ndash5298 2008

[20] M Burgos andM Langlet ldquoThe sol-gel transformation of TIPTcoatings a FTIR studyrdquo Thin Solid Films vol 349 no 1-2 pp19ndash23 1999

[21] P Roy J R Ota and S K Srivastava ldquoCrystalline ZnS thin filmsby chemical bath deposition method and its characterizationrdquoThin Solid Films vol 515 no 4 pp 1912ndash1917 2006

[22] N Naghavi R Henriquez V Laptev and D Lincot ldquoGrowthstudies and characterisation of In2S3 thin films deposited byatomic layer deposition (ALD)rdquo Applied Surface Science vol222 no 1ndash4 pp 65ndash73 2004

[23] E Karber K Otto A Katerski A Mere and M KrunksldquoRaman spectroscopic study of In2S3 films prepared by spraypyrolysisrdquo Materials Science in Semiconductor Processing vol25 pp 137ndash142 2014

[24] J E House Principles of Chemical Kinetics Elsevier Press 2007[25] P Simoncic and T Armbruster ldquoCationic methylene blue

incorporated into zeolite mordenite-Na a single crystal X-raystudyrdquo Microporous and Mesoporous Materials vol 81 no 1ndash3pp 87ndash95 2005

[26] T Zhang T Oyama A Aoshima H Hidaka J Zhao and NSerpone ldquoPhotooxidative N-demethylation of methylene bluein aqueous TiO2 dispersions under UV irradiationrdquo Journal ofPhotochemistry and Photobiology A Chemistry vol 140 no 2pp 163ndash172 2001

Submit your manuscripts athttpswwwhindawicom

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Inorganic ChemistryInternational Journal of

Hindawi Publishing Corporation httpwwwhindawicom Volume 201

International Journal ofInternational Journal ofPhotoenergy

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Carbohydrate Chemistry

International Journal ofInternational Journal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Journal of

Chemistry

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Advances in

Physical Chemistry

Hindawi Publishing Corporationhttpwwwhindawicom

Analytical Methods in Chemistry

Journal of

Volume 2014

Bioinorganic Chemistry and ApplicationsHindawi Publishing Corporationhttpwwwhindawicom Volume 2014

SpectroscopyInternational Journal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

The Scientific World JournalHindawi Publishing Corporation httpwwwhindawicom Volume 2014

Medicinal ChemistryInternational Journal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Chromatography Research International

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Applied ChemistryJournal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Theoretical ChemistryJournal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Journal of

Spectroscopy

Analytical ChemistryInternational Journal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Journal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Quantum Chemistry

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Organic Chemistry International

ElectrochemistryInternational Journal of

Hindawi Publishing Corporation httpwwwhindawicom Volume 2014

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

CatalystsJournal of

Page 4: Methylene Blue Photocatalytic Degradation under Visible ...downloads.hindawi.com/archive/2017/6358601.pdf · ResearchArticle Methylene Blue Photocatalytic Degradation under Visible

4 Advances in Physical Chemistry

0 20 40 60 80 100

Time (min)

CeC

o

50 ppm MB30 ppm MB

20 ppm MB10 ppm MB

0

0102030405060708091

Figure 4 Adsorption process of In2S3 powder (0025 g) at differentMB loads

0 10 20 30 40

ExperimentalLangmuir

0

5

10

15

20

25

30

q (m

gg)

Ce (mgL)

Figure 5 Langmuir and Freundlichmodel fitting toMB adsorptionon In2S3 powder

Table 1 Linear fitting experimental results

Model Parameter(unit) Value

Langmuir119876119898 (mgg)119870 (Lg)1198772

253070979

Freundlich1198991198961198772

58320627

In2S3 adsorption on dark stirring occurs until 60 minutesafter that visible irradiation begins and significant increasein photocatalytic activity was observed Adsorption and

Time (min)

Time (min)

CtC

o

60

70 80 90

100

110

120

130

ln(C

tC

o)

0

01

02

03

04

05

06

07

08

09

1

minus21minus19minus17minus15minus13minus11minus09minus07minus05

Adsorption process Irradiation Photocatalytic process

0 20 40 60 80 100 120 140

Figure 6 MB removal yield in dark stirring and under visible lightirradiation

photomineralization rate of methylene blue followed theLangmuirndashHinshelwood (L-H) kinetics model [25]

V = minus119889 [MB]119889119905= minus 119896119870 [MB]1 + 119870 [MB]

(6)

where V is the rate of dyemineralization 119896 is the rate constant[MB] is the methylene blue concentration and 119870 is theadsorption coefficient Equation (6) can be solved explicitlyfor (119905) for using discrete changes in [MB] from the initialconcentration to a zero reference point In our case anapparent first-order model can be assumed

V = minus119889 [MB]119889119905= 1198961015840 [MB] = 119896119870 [MB] (7)

Integration result in ((6) and (7)) is as follows

[MB] = [MB]119900 119890minus1198961015840119905 (8)

where (119905) is time in minutes and 1198961015840 is the apparent reactionrate constant (minminus1) the assumption of a pseudo-first-ordermodel was used in several studies to characterize the effectof different experimental conditions on the degradation rate[26]

Figure 6 shows change of methylene blue removal yieldboth in dark stirring and under visible light illuminationinside we show pseudo-first-order model fitting Figure 6shows after 60 minutes a plateau zone is reached under darkstirring after that under visible irradiation system reaches86 of MB concentration reduction this 26 could beassigned to photocatalytic processThese results indicate thatIn2S3 has photocatalytic properties under visible irradiationThe 1198961015840 value for In2S3 was established from the slope of thelinear fitting of ln(MBMB119900) versus time We obtained a 1198961015840value of 24 times 10minus2minminus1 This is a significant result due topossibility of using visible radiation directly under catalystswithout physical or chemical modification as TiO2 requiredto be photocatalytically active under visible irradiation

Advances in Physical Chemistry 5

4 Conclusions

We synthesized In2S3 by CBD process Structural character-ization indicated that catalyst powder was polycrystallinebesides optical analysis indicated that compound was activein visible region of electromagnetic spectrum it had a bandgap of 247 eV Furthermore Langmuir adsorption modeldescribed equilibrium adsorption of MB on In2S3 FinallyIn2S3 had photocatalytic activity on MB degradation resultsindicated that MB load reduced 26 after visible illumina-tion

Conflicts of Interest

The authors declare that they have no conflicts of interest

Acknowledgments

This research was supported by Universidad del Atlantico(Project Code CB20-FGI2016)

References

[1] M Mehrjouei S Muller and D Moller ldquoA review on photo-catalytic ozonation used for the treatment of water and wastew-aterrdquo Chemical Engineering Journal vol 263 pp 209ndash219 2015

[2] M Juntti D Russel and J Turnpenny ldquoEvidence politics andpower in public policy for the environmentrdquo EnvironmentalScience and Policy vol 12 no 3 pp 207ndash215 2009

[3] K AnnanWater for People Water for Life Executive Summaryof the UNWorld Development Report UNESCO-WWAP 2003

[4] A Ahmadi and L Tiruta-Barna ldquoA process modelling-life cycleassessment-multiobjective optimization tool for the eco-designof conventional treatment processes of potable waterrdquo Journalof Cleaner Production vol 100 pp 116ndash125 2015

[5] C V Gomez-Pacheco J Rivera-Utrilla M Sanchez-Polo and JJ Lopez-Penalver ldquoOptimization of the preparation process ofbiological sludge adsorbents for application inwater treatmentrdquoJournal of Hazardous Materials vol 217-218 pp 76ndash84 2012

[6] P Wang N Xu and J Shi ldquoA pilot study of the treatment ofwaste rolling emulsion using zirconia microfiltration mem-branesrdquo Journal ofMembrane Science vol 173 no 2 pp 159ndash1662000

[7] R Tarpagkou and A Pantokratoras ldquoThe influence of lamellarsettler in sedimentation tanks for potable water treatmentmdashacomputational fluid dynamic studyrdquo Powder Technology vol268 no 1 pp 139ndash149 2014

[8] E Repo M Makinen S Rengaraj G Natarajan A Bhatnagarand M Sillanpaa ldquoLepidocrocite and its heat-treated formsas effective arsenic adsorbents in aqueous mediumrdquo ChemicalEngineering Journal vol 180 pp 159ndash169 2012

[9] D Li Q Zhu C Han Y Yang W Jiang and Z Zhang ldquoPhoto-catalytic degradation of recalcitrant organic pollutants in waterusing a novel cylindrical multi-column photoreactor packedwith TiO2-coated silica gel beadsrdquo Journal of Hazardous Mate-rials vol 285 pp 398ndash408 2015

[10] B AWols andCHMHofman-Caris ldquoReview of photochem-ical reaction constants of organic micropollutants required forUVadvanced oxidation processes inwaterrdquoWater Research vol46 no 9 pp 2815ndash2827 2012

[11] Z Wang X Liu W Li H Wang and H Li ldquoEnhancing thephotocatalytic degradation of salicylic acid by using molecularimprinted S-doped TiO2 under simulated solar lightrdquo CeramicsInternational vol 40 no 6 pp 8863ndash8867 2014

[12] M V Dozzi and E Selli ldquoDoping TiO2 with p-block elementseffects on photocatalytic activityrdquo Journal of Photochemistry andPhotobiology C Photochemistry Reviews vol 14 no 1 pp 13ndash282013

[13] G R Gopinatha R W Milesb and K T R Reddya ldquoInfluenceof bath temperature on the properties of In2S3 films grown bychemical bath depositionrdquo Energy Procedia vol 34 pp 399ndash406 2013

[14] W Wang G Huang J C Yu and P K Wong ldquoAdvances inphotocatalytic disinfection of bacteria development of photo-catalysts and mechanismsrdquo Journal of Environmental Sciencesvol 34 pp 232ndash247 2015

[15] T Sall B M Soucase M Mollar B Hartitti and M FahoumeldquoChemical spray pyrolysis of 120573-In2S3 thin films deposited atdifferent temperaturesrdquo Journal of Physics and Chemistry ofSolids vol 76 pp 100ndash104 2015

[16] R Lucena F Fresno and J C Conesa ldquoSpectral response andstability of In2S3 as visible light-active photocatalystrdquo CatalysisCommunications vol 20 pp 1ndash5 2012

[17] J Chen W Liu and W Gao ldquoTuning photocatalytic activityof In2S3 broadband spectrum photocatalyst based on morphol-ogyrdquo Applied Surface Science vol 368 pp 288ndash297 2016

[18] R Bayon and J Herrero ldquoStructure and morphology of theindium hydroxy sulphide thin filmsrdquo Applied Surface Sciencevol 158 no 1 pp 49ndash57 2000

[19] N Revathi P Prathap and K T R Reddy ldquoSynthesis andphysical behaviour of In2S3 filmsrdquo Applied Surface Science vol254 no 16 pp 5291ndash5298 2008

[20] M Burgos andM Langlet ldquoThe sol-gel transformation of TIPTcoatings a FTIR studyrdquo Thin Solid Films vol 349 no 1-2 pp19ndash23 1999

[21] P Roy J R Ota and S K Srivastava ldquoCrystalline ZnS thin filmsby chemical bath deposition method and its characterizationrdquoThin Solid Films vol 515 no 4 pp 1912ndash1917 2006

[22] N Naghavi R Henriquez V Laptev and D Lincot ldquoGrowthstudies and characterisation of In2S3 thin films deposited byatomic layer deposition (ALD)rdquo Applied Surface Science vol222 no 1ndash4 pp 65ndash73 2004

[23] E Karber K Otto A Katerski A Mere and M KrunksldquoRaman spectroscopic study of In2S3 films prepared by spraypyrolysisrdquo Materials Science in Semiconductor Processing vol25 pp 137ndash142 2014

[24] J E House Principles of Chemical Kinetics Elsevier Press 2007[25] P Simoncic and T Armbruster ldquoCationic methylene blue

incorporated into zeolite mordenite-Na a single crystal X-raystudyrdquo Microporous and Mesoporous Materials vol 81 no 1ndash3pp 87ndash95 2005

[26] T Zhang T Oyama A Aoshima H Hidaka J Zhao and NSerpone ldquoPhotooxidative N-demethylation of methylene bluein aqueous TiO2 dispersions under UV irradiationrdquo Journal ofPhotochemistry and Photobiology A Chemistry vol 140 no 2pp 163ndash172 2001

Submit your manuscripts athttpswwwhindawicom

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Inorganic ChemistryInternational Journal of

Hindawi Publishing Corporation httpwwwhindawicom Volume 201

International Journal ofInternational Journal ofPhotoenergy

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Carbohydrate Chemistry

International Journal ofInternational Journal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Journal of

Chemistry

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Advances in

Physical Chemistry

Hindawi Publishing Corporationhttpwwwhindawicom

Analytical Methods in Chemistry

Journal of

Volume 2014

Bioinorganic Chemistry and ApplicationsHindawi Publishing Corporationhttpwwwhindawicom Volume 2014

SpectroscopyInternational Journal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

The Scientific World JournalHindawi Publishing Corporation httpwwwhindawicom Volume 2014

Medicinal ChemistryInternational Journal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Chromatography Research International

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Applied ChemistryJournal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Theoretical ChemistryJournal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Journal of

Spectroscopy

Analytical ChemistryInternational Journal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Journal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Quantum Chemistry

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Organic Chemistry International

ElectrochemistryInternational Journal of

Hindawi Publishing Corporation httpwwwhindawicom Volume 2014

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

CatalystsJournal of

Page 5: Methylene Blue Photocatalytic Degradation under Visible ...downloads.hindawi.com/archive/2017/6358601.pdf · ResearchArticle Methylene Blue Photocatalytic Degradation under Visible

Advances in Physical Chemistry 5

4 Conclusions

We synthesized In2S3 by CBD process Structural character-ization indicated that catalyst powder was polycrystallinebesides optical analysis indicated that compound was activein visible region of electromagnetic spectrum it had a bandgap of 247 eV Furthermore Langmuir adsorption modeldescribed equilibrium adsorption of MB on In2S3 FinallyIn2S3 had photocatalytic activity on MB degradation resultsindicated that MB load reduced 26 after visible illumina-tion

Conflicts of Interest

The authors declare that they have no conflicts of interest

Acknowledgments

This research was supported by Universidad del Atlantico(Project Code CB20-FGI2016)

References

[1] M Mehrjouei S Muller and D Moller ldquoA review on photo-catalytic ozonation used for the treatment of water and wastew-aterrdquo Chemical Engineering Journal vol 263 pp 209ndash219 2015

[2] M Juntti D Russel and J Turnpenny ldquoEvidence politics andpower in public policy for the environmentrdquo EnvironmentalScience and Policy vol 12 no 3 pp 207ndash215 2009

[3] K AnnanWater for People Water for Life Executive Summaryof the UNWorld Development Report UNESCO-WWAP 2003

[4] A Ahmadi and L Tiruta-Barna ldquoA process modelling-life cycleassessment-multiobjective optimization tool for the eco-designof conventional treatment processes of potable waterrdquo Journalof Cleaner Production vol 100 pp 116ndash125 2015

[5] C V Gomez-Pacheco J Rivera-Utrilla M Sanchez-Polo and JJ Lopez-Penalver ldquoOptimization of the preparation process ofbiological sludge adsorbents for application inwater treatmentrdquoJournal of Hazardous Materials vol 217-218 pp 76ndash84 2012

[6] P Wang N Xu and J Shi ldquoA pilot study of the treatment ofwaste rolling emulsion using zirconia microfiltration mem-branesrdquo Journal ofMembrane Science vol 173 no 2 pp 159ndash1662000

[7] R Tarpagkou and A Pantokratoras ldquoThe influence of lamellarsettler in sedimentation tanks for potable water treatmentmdashacomputational fluid dynamic studyrdquo Powder Technology vol268 no 1 pp 139ndash149 2014

[8] E Repo M Makinen S Rengaraj G Natarajan A Bhatnagarand M Sillanpaa ldquoLepidocrocite and its heat-treated formsas effective arsenic adsorbents in aqueous mediumrdquo ChemicalEngineering Journal vol 180 pp 159ndash169 2012

[9] D Li Q Zhu C Han Y Yang W Jiang and Z Zhang ldquoPhoto-catalytic degradation of recalcitrant organic pollutants in waterusing a novel cylindrical multi-column photoreactor packedwith TiO2-coated silica gel beadsrdquo Journal of Hazardous Mate-rials vol 285 pp 398ndash408 2015

[10] B AWols andCHMHofman-Caris ldquoReview of photochem-ical reaction constants of organic micropollutants required forUVadvanced oxidation processes inwaterrdquoWater Research vol46 no 9 pp 2815ndash2827 2012

[11] Z Wang X Liu W Li H Wang and H Li ldquoEnhancing thephotocatalytic degradation of salicylic acid by using molecularimprinted S-doped TiO2 under simulated solar lightrdquo CeramicsInternational vol 40 no 6 pp 8863ndash8867 2014

[12] M V Dozzi and E Selli ldquoDoping TiO2 with p-block elementseffects on photocatalytic activityrdquo Journal of Photochemistry andPhotobiology C Photochemistry Reviews vol 14 no 1 pp 13ndash282013

[13] G R Gopinatha R W Milesb and K T R Reddya ldquoInfluenceof bath temperature on the properties of In2S3 films grown bychemical bath depositionrdquo Energy Procedia vol 34 pp 399ndash406 2013

[14] W Wang G Huang J C Yu and P K Wong ldquoAdvances inphotocatalytic disinfection of bacteria development of photo-catalysts and mechanismsrdquo Journal of Environmental Sciencesvol 34 pp 232ndash247 2015

[15] T Sall B M Soucase M Mollar B Hartitti and M FahoumeldquoChemical spray pyrolysis of 120573-In2S3 thin films deposited atdifferent temperaturesrdquo Journal of Physics and Chemistry ofSolids vol 76 pp 100ndash104 2015

[16] R Lucena F Fresno and J C Conesa ldquoSpectral response andstability of In2S3 as visible light-active photocatalystrdquo CatalysisCommunications vol 20 pp 1ndash5 2012

[17] J Chen W Liu and W Gao ldquoTuning photocatalytic activityof In2S3 broadband spectrum photocatalyst based on morphol-ogyrdquo Applied Surface Science vol 368 pp 288ndash297 2016

[18] R Bayon and J Herrero ldquoStructure and morphology of theindium hydroxy sulphide thin filmsrdquo Applied Surface Sciencevol 158 no 1 pp 49ndash57 2000

[19] N Revathi P Prathap and K T R Reddy ldquoSynthesis andphysical behaviour of In2S3 filmsrdquo Applied Surface Science vol254 no 16 pp 5291ndash5298 2008

[20] M Burgos andM Langlet ldquoThe sol-gel transformation of TIPTcoatings a FTIR studyrdquo Thin Solid Films vol 349 no 1-2 pp19ndash23 1999

[21] P Roy J R Ota and S K Srivastava ldquoCrystalline ZnS thin filmsby chemical bath deposition method and its characterizationrdquoThin Solid Films vol 515 no 4 pp 1912ndash1917 2006

[22] N Naghavi R Henriquez V Laptev and D Lincot ldquoGrowthstudies and characterisation of In2S3 thin films deposited byatomic layer deposition (ALD)rdquo Applied Surface Science vol222 no 1ndash4 pp 65ndash73 2004

[23] E Karber K Otto A Katerski A Mere and M KrunksldquoRaman spectroscopic study of In2S3 films prepared by spraypyrolysisrdquo Materials Science in Semiconductor Processing vol25 pp 137ndash142 2014

[24] J E House Principles of Chemical Kinetics Elsevier Press 2007[25] P Simoncic and T Armbruster ldquoCationic methylene blue

incorporated into zeolite mordenite-Na a single crystal X-raystudyrdquo Microporous and Mesoporous Materials vol 81 no 1ndash3pp 87ndash95 2005

[26] T Zhang T Oyama A Aoshima H Hidaka J Zhao and NSerpone ldquoPhotooxidative N-demethylation of methylene bluein aqueous TiO2 dispersions under UV irradiationrdquo Journal ofPhotochemistry and Photobiology A Chemistry vol 140 no 2pp 163ndash172 2001

Submit your manuscripts athttpswwwhindawicom

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Inorganic ChemistryInternational Journal of

Hindawi Publishing Corporation httpwwwhindawicom Volume 201

International Journal ofInternational Journal ofPhotoenergy

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Carbohydrate Chemistry

International Journal ofInternational Journal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Journal of

Chemistry

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Advances in

Physical Chemistry

Hindawi Publishing Corporationhttpwwwhindawicom

Analytical Methods in Chemistry

Journal of

Volume 2014

Bioinorganic Chemistry and ApplicationsHindawi Publishing Corporationhttpwwwhindawicom Volume 2014

SpectroscopyInternational Journal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

The Scientific World JournalHindawi Publishing Corporation httpwwwhindawicom Volume 2014

Medicinal ChemistryInternational Journal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Chromatography Research International

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Applied ChemistryJournal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Theoretical ChemistryJournal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Journal of

Spectroscopy

Analytical ChemistryInternational Journal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Journal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Quantum Chemistry

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Organic Chemistry International

ElectrochemistryInternational Journal of

Hindawi Publishing Corporation httpwwwhindawicom Volume 2014

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

CatalystsJournal of

Page 6: Methylene Blue Photocatalytic Degradation under Visible ...downloads.hindawi.com/archive/2017/6358601.pdf · ResearchArticle Methylene Blue Photocatalytic Degradation under Visible

Submit your manuscripts athttpswwwhindawicom

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Inorganic ChemistryInternational Journal of

Hindawi Publishing Corporation httpwwwhindawicom Volume 201

International Journal ofInternational Journal ofPhotoenergy

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Carbohydrate Chemistry

International Journal ofInternational Journal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Journal of

Chemistry

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Advances in

Physical Chemistry

Hindawi Publishing Corporationhttpwwwhindawicom

Analytical Methods in Chemistry

Journal of

Volume 2014

Bioinorganic Chemistry and ApplicationsHindawi Publishing Corporationhttpwwwhindawicom Volume 2014

SpectroscopyInternational Journal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

The Scientific World JournalHindawi Publishing Corporation httpwwwhindawicom Volume 2014

Medicinal ChemistryInternational Journal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Chromatography Research International

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Applied ChemistryJournal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Theoretical ChemistryJournal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Journal of

Spectroscopy

Analytical ChemistryInternational Journal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Journal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Quantum Chemistry

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Organic Chemistry International

ElectrochemistryInternational Journal of

Hindawi Publishing Corporation httpwwwhindawicom Volume 2014

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

CatalystsJournal of