research article structural, electrical, dielectric, and magnetic properties...

Research ArticleStructural Electrical Dielectric and Magnetic Properties ofCd2+ Substituted Nickel Ferrite Nanoparticles

B H Devmunde1 A V Raut1 S D Birajdar2 S J Shukla3

D R Shengule1 and K M Jadhav2

1Vivekanand Arts Sardar Dalipsingh Commerce and Science College Aurangabad 431001 India2Department of Physics Dr Babasaheb Ambedkar Marathwada University Aurangabad 431001 India3Department of Physics PG Research Centre Deogiri College Aurangabad 431001 India

Correspondence should be addressed to A V Raut dravrautgmailcom

Received 10 October 2015 Revised 7 January 2016 Accepted 13 January 2016

Academic Editor Raphael Schneider

Copyright copy 2016 B H Devmunde et al This is an open access article distributed under the Creative Commons AttributionLicense which permits unrestricted use distribution and reproduction in any medium provided the original work is properlycited

In the present investigation structural electric magnetic and frequency dependent dielectric properties of Ni1minus119909

Cd119909Fe2O4ferrite

nanoparticles (NPs) (where 119909 = 02 04 06 and 08) prepared by sol-gel autocombustion method were studiedThe crystallite size(119905) (4689sim5840 nm)was estimated fromX-ray diffraction datawith the postconfirmation of single phase spinel structure Sphericalshaped fused grain nature with intergranular diffusion in Ni

1minus119909Cd119909Fe2O4NPs was observed in scanning electron micrographs

The value of loss tangent (tan 120575) decreases exponentially with an increasing frequency indicating normal Maxwell-Wagner typedielectric dispersion due to interfacial polarization Decreasing values of Curie temperature (119879

119862) from 860∘C to 566∘C with

increasing Cd2+ content 119909 in Ni1minus119909

Cd119909Fe2O4NPs were determined from AC-Susceptibility Activation energy Δ119864 ranges within

003sim015 eV Decreasing magnetic saturation119872119904 coercivity119867

119888 and magneton number 119899B values show the effect on nonmagnetic

Cd2+ ions over magnetic Ni2+ and Fe ions

1 Introduction

With the striking feature of ldquoferrimagnetismrdquo nanocrystallineferrites have attracted special attention of researchers in thefield of electronic technology Ceramics of ferrite have a widetemperature range of minus40 to +225∘C and greater values ofspecific resistivity and dielectric constant than that of themetals [1] The unit cell contains eight formula units and isusually referred to as space group Fd3m (O7h) with the cationsoccupying special positions 8a and 16d The ideal structureconsists of cubic close packing of oxygen atoms (32e) inwhichone-eighth of the tetrahedral (A) and half of the octahedral[B] interstices are occupied [2] The unit-cell geometry iscontrolled by only the metal-oxygen bond lengths for thetetrahedral (AndashO) and octahedral [BndashO] sites (Hill et al 1979)[3] In normal spinel structure the cation distribution is pro-posed as (M2+)A(M3+M3+)BO

4while inverse spinel has the

general formula (M3+)A(M2+M3+)BO4 The nonconvergent

disorder of cations over the tetrahedral (A) and octahedral[B] sites can be described using an inversion parameter (120575)and the formula (M2+

1minus120575M3+120575)A[M2+120575M3+2minus120575

]BO4 where

120575 = 0 for an extreme case and 120575 = 1 for a completely inversespinel [3 4] NiFe

2O4NPs (cubic 119886 = 8327 A plusmn 0002gt)

(F41d32m number 227 in International Tables) [5] 119885 = 8

JCPDS PDF-10-0325 is a semiconductor having a room-temperature resistivity sim1 kΩ cm and shows soft ferromag-netic order below 850K with a relatively low magnetizationof 2120583B per formula unit that is about 300 emu cmminus3 Cd2+ isa nonmagnetic (0 120583B) divalent ion that shows almost similarsubstitution behaviour as that of Zn2+ substitution in ferrites[6] Mixed Cd-ferrites (JCPDS-79-1155 [7]) are technicallyimportant due to their high resistivity high permeabilityand comparatively low magnetic losses making them moresuitable for the electrical switching applications [8ndash10] Cd2+substituted NiFe

2O4NPs have widespread applications in

recording heads antenna rods loading coils microwave

Hindawi Publishing CorporationJournal of NanoparticlesVolume 2016 Article ID 4709687 8 pageshttpdxdoiorg10115520164709687

2 Journal of Nanoparticles

devices [1 7] multilayer chip inductor (MLCI) [11] highfrequency transformer cores phase shifter resonators com-puters TVs and mobile phones [12ndash16] The spinel structureof NiFe

2O4NPs is constructed by filling the FCC sublattice

of relatively larger oxygen ions and the cation distribution isstrongly dependent on ionic radii as well as concentrationof the substituted divalent metal ions [17] The entire Ni2+cations occupy the [B]-site while the Fe3+ cations distributeequally between (A)-site and [B]-sites Angle AndashOndashB is closerto 180∘ than the angles BndashOndashB and AndashOndashA therefore the ABpair (FendashFe) has a strong antiferromagnetic superexchangeinteraction [18] Postsubstitution site preferences of Cd2+ions are towards the tetrahedral (A) site suggesting thedistribution of cations as

(Cd2+119909Fe3+1minus119909

)

A[Ni2+1minus119909

Fe3+1+119909

]

BO2minus4

(1)

Several possible cation distributions and various magneticorders can be studied at A B1 and B2 sites [19] Nath etal have studied the magnetic orders in Ni-Cd ferrite [6] Inrecent days variety of chemical and physical methods hasbeen employed for the preparation of well-defined magneticNi-Cd ferrite NPs with specific shape and size Rafeek etal have synthesised Ni-Cd NPs by sol-gel autocombustionmethod for the study of the antibacterial effects againstmicroorganism [8 20] Nejati et al have discussed thesuperparamagnetic nature of NiFe

2O4NPs synthesised by

hydrothermal method [11 21] Drmota has discussed theprecipitation in microemulsion method for the controlledsize and morphology of magnetic nanoparticles [22] Sureshet al have prepared Ni-Cd NPs with crystallite size of 15sim23 nm using chemical coprecipitation method [23] Modi etal have studied the pre- and postannealing particle size ofthe Ni-Cd ferrite NPs synthesis by wet-chemical technique[24] Rahimi et al have reported the synthesis of nanoscaleNi1minus119909

Cd119909Fe2O4ferrite powders by sol-gel autocombustion

method using EDTAas a complexion agent [25] In this inves-tigation we have applied sol-gel autocombustion methodfor the production of fine powder of Ni

1minus119909Cd119909Fe2O4NPs

This preparation technique involves the exothermic andself-sustaining thermally induced anionic redox reaction ofaerogel which is obtained from aqueous solution [26]

2 Experimental Details

21 Synthesis of1198731198941minus11990911986211988911990911986511989021198744 NPs Ni1minus119909Cd119909Fe2O4 spinelferrite NPs (where 119909 = 02 04 06 and 08) were pre-pared successfully by sol-gel autocombustion method usingstoichiometric proportion of 999 pure AR grade ferricnitrate (Fe(NO

3)3sdot9H2O) nickel nitrate (Ni(NO

3)2sdot6H2O)

and cadmium nitrate (Fe(NO3)2sdot4H2O) (gt99) as starting

materials The metal nitrates were dissolved together in thepresence of minimum amount of double distilled deionizedwater Citric acid (C

6H8O7) is significantly used in wet-

chemical methods compared to the other fuels as it ischaracteristically weak organic acid having better complexingability possessing a low ignition temperature (200ndash250∘C)The molar ratio of metal nitrates to citric acid (C

6H8O7) was

taken as 1 3The pH of the solution was maintained at 7 with

the drop by drop addition of ammonia solution Continuousstirring of the mixed nitrate aqueous solution was performedon a magnetic hot-plate stirrer maintaining the temperature90∘CDuring the evaporation stages solution became viscousin colour and later on formed a viscous brown gel Finally astickymass began to bubble for fewminutes in a same beakerThis gel got ignited automatically and burned with a glowingflint The decomposition process would not stop before thewhole citrate complex was consumed As a yield productof this reaction fluffy loose powder of brown colouredash could be termed as Ni

1minus119909Cd119909Fe2O4presintered ferrite

The prepared samples were dried and annealed at 800∘Cfor 12 h after thermogravimetric analysis (TGA) Some partof the annealed Ni

1minus119909Cd119909Fe2O4NPs was granulated with

the addition of saturated PVA solution (polyvinyl alcohol(C2H4O)119909) as a binder These granulated NPs were used to

prepare disc shaped pellets of 10mm diameter and 3mmthickness using the hydraulic press by applying pressure of5 tonscm2 for 5min in a stainless steel die

3 Results and Discussion

31 X-Ray Diffraction Study of 1198731198941minus11990911986211988911990911986511989021198744 NPs X-raydiffraction patterns of Ni

1minus119909Cd119909Fe2O4NPs were recorded

with the X-ray diffractometer (Philips) XRD of all sampleswere recorded in the 2120579 range of 20ndash80∘ withCu-K120572 radiation(120582 = 15405 au) at room temperature All the peaks wereidentified by comparing the ldquo119889rdquo spacing with that of JCPDSdata of NiFe

2O4and CdFe

2O4in order to confirm the

crystalline phases present The major lattice planes (220)(311) (400) (422) (511) and (440) in Figure 1 confirm theformation of single phase Ni

1minus119909Cd119909Fe2O4with a face centred

cubic spinel structure space group Fd3mAccordinglyminorlattice planes (222) (533) (622) and (444) in XRD patterngave supporting agreement about the powder diffractionof the spinel cubic JCPDS [27] Cation distribution wasestimated from the comparison between observed intensityratios (119868obs) and calculated intensity ratios (119868cal) by followingthe Bertaut method [12] The values of structural parameterslike peak intensity ratios hopping length (119871A 119871B) and bondlength (119877A 119877B) are depicted in Table 1 Lattice constant (119886)of Ni1minus119909

Cd119909Fe2O4NPs (Table 1) was determined from X-ray

data analysis with an accuracy of plusmn0002gt using the formula[28]

119886 = 119889radic(ℎ2+ 1198962+ 1198972) (2)

where 119886 is a lattice constant (ℎ 119896 119897) represents the Millerindices 120582 is a wavelength of X-rays and 120579 is the glancingangle It can be noticed from Figure 2 that the value of latticeparameter increased with the increase in Cd2+ content [29]from 8350 A to 8491 A (plusmn0002gt) which is attributed to thelarger ionic radius of Cd2+ (097 A) ions than that of Ni2+(078 A) ions obeyingVegardrsquos law [12] Crystallite size (119905) wasdetermined by using the Scherrer formula [30]

119905 =

089120582

120573 cos 120579 (3)

Journal of Nanoparticles 3

Table 1 Cation distribution hopping length (119871A and 119871B) and bond length (119877A and 119877B) of Ni1minus119909Cd119909Fe2O4 NPs

Cd (119909) Ni1minus119909

Cd119909Fe2O4

119868(220)

119868(440)

119868(400)

119868(422)

119868(400)

119868(440)

119871A (A) 119871B (A) 119877A (A) 119877B (A)119868cal 119868obs 119868cal 119868obs 119868cal 119868obs

02 (Cd02Fe08)A[Ni

08Fe12]B 0756 0872 131 193 0351 0578 3615 2951 1894 2038

04 (Cd04Fe06)A [Ni

06Fe14]B 0912 0776 074 109 0250 0464 3621 2956 1897 2041

06 (Cd06Fe04)A [Ni

04Fe16]B 1099 0964 043 113 0174 0397 3633 2966 1904 2048

08 (Cd08Fe02)A [Ni

02Fe18]B 1261 1226 0114 0571 025 067 3676 3001 1926 2072

Table 2 Lattice constant 119886 crystallite size 119905 X-ray density119889X porosity119875 activation energyΔ119864 andCurie temperature119879119862ofNi1minus119909

Cd119909Fe2O4

NPs

Cd (119909) 119886 (plusmn0002 A) 119905 (plusmn1 nm) 119889X (plusmn0002 gcm3) 119875 119864119875(eV) 119864

119891(eV) Δ119864 plusmn 119864

119875minus 119864119865(eV) 119879

119862

∘C02 8350 4689 5593 3920 038 034 004 86004 8363 4870 5811 4029 021 018 003 79706 8390 5530 5995 3952 04 027 015 76608 8491 5840 6017 3817 034 028 006 566

Inte

nsity

(au

)

02 04

06

(622

)(5

33)

(444

)

08

(220

) (311

)(2

22) (400

)

(422

) (511

)

(440

)

30 40 50 60 70 80202120579 (deg)

Figure 1 X-ray diffraction pattern of Ni1minus119909

Cd119909Fe2O4NPs for 119909 =

02 04 06 and 08

where 119905 is a crystallite size (nm) 120573 is a full width athalf maximum of strongest diffraction peak (311) 120582 is awavelength of X-ray and 120579 is the diffraction angle Crystallitesize ofNi

1minus119909Cd119909Fe2O4NPswas lying in the range of 4689 nm

to 5840 nm (Table 2)There is a common trend of increasingcrystallite size 119905 with increase in sintering temperature

aEP

EP

EF

EF

015

018

021

024

027

030

033

036

039

042

EP

-EF

(eV

)

04 06 0802Cd2+ content x

834

836

838

840

842

844

846

848

850

Latti

ce co

nsta

nt a

(Aring)

Figure 2 Lattice constant 119886 and activation energies 119864119875and 119864

119865in

paramagnetic region and ferrimagnetic region for Ni1minus119909

Cd119909Fe2O4

NPs

Usually increasing crystallite size in ferrite nanoparticlesdecreases the magnetic property because a large grain sizeleads to a low signal to noise ratio [31] X-ray density (119889X)was calculated using the relation [32]

119889X =

8119872

(119873A1198863)

(4)

where 119872 is a molecular mass and 119873A is Avogadrorsquos number(119873A = 602 times 1023) It was clear from Table 2 that X-raydensity (119889X) of Ni1minus119909Cd119909Fe2O4NPs increases with increasingCd2+ content 119909 from 5593 gcm3 to 6017 gcm3 From X-raydensity (119889X) and bulk density values (119889B) the pore volumedistribution (119875) was calculated (Table 2) using followingrelation

119875 = (

119889X minus 119889B119889X

) times 100 (5)


Figure 3 Scanning electron micrographs of Ni1minus119909

Cd119909Fe2O4NPs for the typical samples 119909 = 02 and 06

The values of percentage porosity ldquo119875rdquo ranges in between 38to 40 The variation in 119875 with increase in Cd2+ content 119909in Ni1minus119909

Cd119909Fe2O4NPs is depicted in Table 2

32 Scanning Electron Microscopy Surface morphology andaverage grain size of Cd2+ substituted Ni


were determined by using analytical scanning electronmicroscope by selecting 10000 magnification range SEMimages (Figure 3) of typical samples (119909 = 02 and 06) showsthe nanocrystalline nature of Ni

1minus119909Cd119909Fe2O4NPs with vivid

pores suggesting it as more advantages for the gas sensingapplications Voids and pores present in Ni


can be attributed to the release of gases during the com-bustion process and lesser the dense nature Intergranulardiffusion can be clearly seen in SEM images of the NPs Fusedgrain nature can be seen in 119909 = 02 whereas 119909 = 06 lookscomparatively more crystalline affecting the spin couplingin Ni1minus119909

Cd119909Fe2O4NPs which is at the base of the magnetic

behaviour

33 DC-Resistivity The resistivity of ferrites ranges from105Ω cm to 109Ω cmat room temperatureTheDC-resistivityin Ni

1minus119909Cd119909Fe2O4NPs arises from the contribution of

crystallite resistivity as well as the resistivity of crystallineboundaries This phenomenon can be described by Verveyrsquoshopping mechanism The electrical conduction in a materialtakes place due to the ions migration and when an externalagency makes the activation of charge carriers As the (A)-site and [B]-site are energetically not equivalent conductivityis mostly dependent upon electron exchange between [B]-site cations [33] The temperature dependence DC-resistivityof Ni1minus119909

Cd119909Fe2O4NPs was measured by two-point probe

technique within the temperature range of 300ndash900K andcalculated using Arrhenius relation [34]

120588 = 120588119900exp(Δ119864119870B119879) (6)

where Δ119864 is an activation energy and 119870B is Boltzmannconstant (138066 times 10minus23 J Kminus1) In ferrites the mobility ofelectron is temperature dependent and it is characterized interms of activation energies The values of activation energyin paramagnetic (119864

119875) and ferrimagnetic region (119864

119865) with

respect to Cd2+ content were calculated from the plots of ln120590versus 1000119879 using following relation [35]

Δ119864 = 1982 times slope of the graph (7)

The low value of activation energy in Ni-Cd ferrites maybe attributed to the creation of small number of oxygenvacancies after doping of Cd2+ content and the decreasingactivation energy may be due to the dominant role ofCd2+ in electrical resistivity of Ni

1minus119909Cd119909Fe2O4NPs [36]

Several researchers have justified such behaviour in nickelcadmium ferrites on the basis of role of ferrous ion con-tent in exchange interactions [37] The minimum valueof ferrous ion concentration in octahedral [B] site playsan important role in Fe2+ harr Fe3+ exchange interactionwhich is significantly responsible for the maximum electricalresistivity and low activation energies in this ferrite [38] Itwas found that the activation energy in paramagnetic regionis maximum compared to that of the ferrimagnetic regionA break separating the curve (Figure 4) in ferromagneticand paramagnetic region indicates the change in magneticorder which is termed as Curie point (119879

119862) The substitution

of nonmagnetic Cd2+ ions in place of magnetic Ni2+ ionsreduces the active linkage Fe3+A harr Fe3+B with increase inCd2+ content 119909 therefore Curie temperature of the systemdecreases with increasingCd2+ substitutionwhich is depictedin Table 2 The value of AC-Susceptibility decreases from860∘C to 566∘Cwith increase in Cd2+ content 119909 An electricalproperty based application of Ni

1minus119909Cd119909Fe2O4NPs includes

transformer cores inductors (SMPS) converters EMI filterspicture tube yoke rotator circulator and phase shifter

34 Dielectric Properties In general the dielectric behaviourof a material depends on the strength of electromagneticinteractions between constituent phases the relative predom-inance of one phase over the other and micro structure ofphases [39] The dielectric constant (1205761015840) and dielectric losstangent (tan 120575) were determined as a function of frequency(100Hz le 119891 le 10MHz) In the present investigation Figures5 and 6 show that 1205761015840 decreases and tan 120575 decreases exponen-tially which corresponds to the decrease in AC-conductivityMore dielectric depression can be observed at the lowerfrequency regionThedielectric behaviour ofNi

1minus119909Cd119909Fe2O4


02

log 120588

(Ωcm

)

16

20

24

28

32

12 13 14 15 1611A

(a) 04

log 120588

(Ωcm

)

46

48

50

52

54

56

13 14 15 1612A

(b)

06

log 120588

(Ωcm

)

08

12

16

20

24

12 13 14 15 16111000T (K)

(c) 08

log 120588

(Ωcm

)

08

10

12

14

16

13 14 15 16121000T (K)

(d)

Figure 4 DC-resistivity plots of Ni1minus119909

Cd119909Fe2O4NPs for 119909 = 02 04 06 and 08

NPs can be explained on the basis of Maxwell-Wagnerinterfacial polarization which is in agreement with Kooprsquosphenomenological theory [40ndash42] In Figure 6 the shoulder-like peaks observed in the variation of tan 120575 with logarithmicfrequency range from 35 to 4 This behaviour reveals thatthe resonance occurs between applied frequencies and hop-ping frequencies of charge carries The maximum values ofdielectric constant 1205761015840 at lower frequenciesmay be attributed tothe polarization due to inhomogeneous dielectric structurenamely porosity and grain boundaries [43] The decrease inpolarizationwith increase in frequencymay be due to the factthat beyond a certain frequency of electric field the electronexchange cannot follow the alternating field and therefore thereal part of the dielectric constant decreases with increase infrequency [24]

35 Magnetic Properties Room-temperature magnetic prop-erties of Ni

1minus119909Cd119909Fe2O4NPs were measured using pulse

field hysteresis loop tracer technique by applying a mag-netic field of 1000Oe Using 119872-119867 plots (see Figure 7)of Ni1minus119909

Cd119909Fe2O4NPs the saturation magnetization (119872

119904)

remanence magnetization (119872119903) coercivity (119867

119888) and square-

ness ratio (119872119903119872119904) were determined From Table 3 it is

evident that magnetic parameters of Ni1minus119909

Cd119909Fe2O4NPs

decrease as a function of cadmium content 119909which is associ-ated with linkage between (A) and [B] sites It may be due tothe fact that nonmagnetic Cd2+ ions (0 120583B) replace magneticNi2+ ions (2120583B) [44] The magneton number increases up to119909 = 04 and then decreases with increasing Cd2+ content 119909According to Neelrsquos two-sublattice model of ferrimagnetismmagnetic moment per formula in 120583B 119899

119873

B is given by

119899119873

B (119883) = 119872B (119883) minus119872A (119883) (8)

where 119872A and 119872B are the [B] and (A) sublattice magneticmoment in 120583B and the values of magnetic moments of Fe3+


Table 3 Abortion band frequencies (1205921and 120592

2) force constant (119870

119905and 119870

0) saturation magnetization119872

119904 coercivity119867

119888 magneton number

119899B and 120572Y-K angle of Ni1minus119909

Cd119909Fe2O4NPs

Cd (119909) 1205921(cmminus1) 120592

2(cmminus1) 119870

119905times 105 (dynecm) 119870

0times 105 (dynecm) 119872

119904(emug) 119867

119888(Oe) 119899B (120583B) 120572Y-K angle (degree)

02 57940 46978 13355 17179 9703 13 258 004 58334 47512 13592 20347 9422 19 257 29∘301015840

06 57919 47766 13669 22950 6611 32 190 53∘431015840

08 mdash mdash mdash mdash 1373 20 042 77∘551015840

02 04

06 08

times104

120576998400

200E minus 010400E minus 010600E minus 010800E minus 010100E minus 009120E minus 009140E minus 009160E minus 009180E minus 009200E minus 009220E minus 009240E minus 009260E minus 009280E minus 009300E minus 009

20 40 60 80 1000Frequency

Figure 5 Dielectric constant (1205761015840) verses frequency ofNi1minus119909

Cd119909Fe2O4NPs

0204

0608

tan 120575

0123456789

10

25 30 35 40 45 50 55 60 6520log F

Figure 6 Dielectric loss tangent tan 120575 verses logarithmic frequencyof Ni1minus119909

Cd119909Fe2O4NPs

Ni2+ andCd2+ were taken as 5 120583B 2 120583B and 0120583B respectivelyNeelrsquos model of two sublattices does not hold good forthe variation in magneton number with Cd2+ content 119909According to the Yafet-Kittel model

120583B = 119872B cos120572Y-K minus119872A (9)

0204

0608

minus5000

minus4000

minus3000

minus2000

minus1000

0

1000

2000

3000

4000

5000

Mag

netiz

atio

n (e

mu

gm)

minus4 minus3 minus2 minus1 0 1 2 3 4 5minus5Applied field (Oe)

minus20

0

20

Mag

netiz

atio

n (e

mu

gm)

00 01minus01Applied field (Oe)

minus2000

minus3000

minus4000

minus5000

Mag

netiz

atio

n (e

mu

gm)

minus41 minus42 minus43 minus44 minus45minus40

Applied field (Oe)

Figure 7 Magnetic hysteresis loops of Ni1minus119909

Cd119909Fe2O4NPs

where 120572 is a Y-K angle In the samples with Cd2+ content119909 = 00 and 02 120572Y-K was found zero From 119909 = 04 to08 120572Y-K increases from 29∘301015840 to 77∘551015840 which is attributedto the increased triangular spin arrangements on octahedral[B] sites [6] These dilutions of spin moments weaken the inA-B interaction as Cd2+ content 119909 increases Fe3+ ions haveno magnetic neighbours and hence spins become uncoupleddecreasing the saturation magnetization (119872

119904) from 9422 to

1373 (emug) which is in agreement with Suresh et al [23]This shows the size dependent behaviour of Ni


NPs [45] Behaviour of coercivity can be explained on thebasis of Brown relation [46]119867

119888= 211989611205830119896119872119904 For 119909= 02ndash06

119867119888increases which is attributed to the uniform grain growth

of single domain particle in which the absence of domainwall makes the magnetization process more difficult [4] Thevalues ofmagneton number 119899B (saturationmagnetization performula unit in 120583B) are depicted in Table 3 For 119909 = 06

maximum value of 119899B was recorded otherwise decreasingnature of 119899B was observed for other samples from 258120583Bto 042 120583B with Cd2+ content 119909 which is associated with adecrease in A-B interaction

4 Conclusions

Ni1minus119909

Cd119909Fe2O4spinel ferrite nanoparticles (NPs) were suc-

cessfully prepared by sol-gel autocombustion technique usingcitric acid as a fuel X-ray diffraction results showed the pres-ence of all characteristic reflections (220) (311) (222) (400)


(422) (511) (440) (222) (533) (622) and (444) which con-firmed the formation of single phase cubic spinel structureLattice constant (119886) X-ray density (119889X) and crystallite size(119905) increase with Cd2+ substitution DC-resistivity decreasescontinuously with the increasing temperature revealing thesemiconducting nature of the prepared Ni-Cd samples 119879

119862

decreases from 860∘C to 566∘Cwith increase in Cd2+ content119909 SEM images show the fused grain naturewith intergranulardiffusion in Ni

1minus119909Cd119909Fe2O4NPs The dielectric constant

(1205761015840) and dielectric loss tangent (tan 120575) decrease exponentiallywhich correspond to the decrease in AC-conductivity Sizedependent behaviour of magnetic parameters shows thedecrease in saturation magnetization (119872

119904) from 9422 to

1373 (emug)

Highlights

(i) Ni1minus119909

Cd119909Fe2O4NPs are synthesised by sol-gel auto-

combustion method(ii) X-ray diffraction pattern confirmed the formation of

spinel structure(iii) 1205761015840 decreases with frequency and tan 120575 decreases expo-

nentially(iv) SEMconfirmed the nanocrystalline naturewith inter-

granular diffusion(v) Magnetic parameters decrease with increasing Cd2+

substitution

Conflict of Interests

The authors declare that there is no conflict of interestsregarding the publication of this paper

Acknowledgment

The authors would like to thank Dr K M Jadhav forhis valuable guidance and research facility for the presentinvestigation

References

[1] G Sabri N ldquoThe outer membrane proteins profile of Salmonellaenterica serotypes Enteritidis Muenster Florian Omuna andNoya and their dendrogram analysisrdquo International Journal ofAdvanced Research vol 2 no 1 pp 182ndash187 2013

[2] J L Martın de Vidales A Lopez-Delgado V Vila and F ALopez ldquoThe effect of the starting solution on the physico-chemical properties of zinc ferrite synthesized at low temper-aturerdquo Journal of Alloys and Compounds vol 287 no 1-2 pp276ndash283 1999

[3] C M B Henderson J M Charnock and D A Plant ldquoCationoccupancies in Mg Co Ni Zn Al ferrite spinels a multi-element EXAFS studyrdquo Journal of Physics Condensed Mattervol 19 Article ID 076214 25 pages 2007

[4] A V Raut D V Kurmude D R Shengule and K M JadhavldquoEffect of gamma irradiation on the structural and magneticproperties of Co-Zn spinel ferrite nanoparticlesrdquo MaterialsResearch Bulletin vol 63 pp 123ndash128 2015

[5] D V Kurmude R S Barkule A V Raut D R Shenguleand K M Jadhav ldquoX-ray diffraction and cation distributionstudies in zinc-substituted nickel ferrite nanoparticlesrdquo Journalof Superconductivity and Novel Magnetism vol 27 no 2 pp547ndash553 2014

[6] S K Nath K H Maria S Noor S S Sikder S M Hoque andM A Hakim ldquoMagnetic ordering in NindashCd ferriterdquo Journal ofMagnetism and Magnetic Materials vol 324 no 13 pp 2116ndash2120 2012

[7] S M Ismail Sh Labib and S S Attallah ldquoPreparation andcharacterization of nano-cadmium ferriterdquo Journal of Ceramicsvol 2013 Article ID 526434 8 pages 2013

[8] K Sinko E Manek A Meiszterics K Havancsak U Vainioand H Peterlik ldquoLiquid-phase syntheses of cobalt ferritenanoparticlesrdquo Journal of Nanoparticle Research vol 14 no 6article 894 2012

[9] S P Dalawai A B Gadkari T J Shinde and P N VasambekarldquoEffect of sintering temperature on structural and electricalswitching properties of cadmium ferriterdquo Advanced MaterialsLetters vol 4 no 7 pp 586ndash590 2013

[10] S Singh S Munjal and N J Khare ldquoStraindefect inducedenhanced coercivity in single domain CoFe

2O4nanoparticlesrdquo

Journal of Magnetism and Magnetic Materials vol 386 pp 69ndash73 2015

[11] M B Shelar P A Jadhav S S Chougule M M Mallapurand B K J Chougule ldquoStructural and electrical properties ofnickel cadmium ferrites prepared through self-propagating autocombustion methodrdquo Journal of Alloys and Compounds vol476 no 1-2 pp 760ndash764 2009

[12] K S Lohar S M Patange M L Mane and S E Shir-sath ldquoCation distribution investigation and characterizationsof Ni

1minus119909Cd119909Fe2O4nanoparticles synthesized by citrate gel

processrdquo Journal of Molecular Structure vol 1032 pp 105ndash1102013

[13] E Ranjith Kumar R Jayaprakash T Arun Kumar and SKumar ldquoEffect of reaction time on particle size and dielectricproperties of manganese substituted CoFe


Journal of Physics and Chemistry of Solids vol 74 no 1 pp 110ndash114 2013

[14] B S Randhawa H S Dosanjh and M Kaur ldquoPreparationof spinel ferrites from citrate precursor routemdasha comparativestudyrdquo Ceramics International vol 35 no 3 pp 1045ndash10492009

[15] M M Karanjkar N L Tarwal A S Vaigankar and P SPatil ldquoStructural Mossbauer and electrical properties of nickelcadmium ferritesrdquo Ceramics International vol 39 no 2 pp1757ndash1764 2013

[16] K M Batoo ldquoMicrostructural and Mossbauer properties oflow temperature synthesized Ni-Cd-Al ferrite nanoparticlesrdquoNanoscale Research Letters vol 6 article 499 2011

[17] T Slatineanu A R Iordan M N Palamaru O F CaltunV Gafton and L Leontie ldquoSynthesis and characterizationof nanocrystalline Zn ferrites substituted with Nirdquo MaterialsResearch Bulletin vol 46 no 9 pp 1455ndash1460 2011

[18] S S R Inbanathan V Vaithyanathan J A Chelvane GMarkandeyulu and K K J Bharathi ldquoMossbauer studies andenhanced electrical properties of R (R=Sm Gd and Dy) dopedNi ferriterdquo Journal of Magnetism and Magnetic Materials vol353 pp 41ndash46 2014

[19] C Cheng ldquoEnhanced magnetization and conductive phase inNiFe2O4rdquo Journal of Magnetism and Magnetic Materials vol

325 pp 144ndash146 2013


[20] K Rafeekali and EMMuhammed ldquoAnti bacterial study of cad-mium substituted nickel ferrite nano particlesrdquo InternationalJournal of Engineering Research and General Science vol 3 no4 pp 2091ndash2730 2015

[21] K Nejati and R Zabihi ldquoPreparation and magnetic proper-ties of nano size nickel ferrite particles using hydrothermalmethodrdquo Chemistry Central Journal vol 6 article 23 2012

[22] A Drmota M Drofenik J Koselj and A ZnidarsicldquoMicroemulsion method for synthesis of magnetic oxidenanoparticlesrdquo in MicroemulsionsmdashAn Introduction toProperties and Applications R Najjar Ed chapter 10 pp191ndash215 InTech Rijeka Croatia 2012

[23] R Suresh P Moganavally and M Deepa ldquoStructural andmagnetic properties of NiCd ferritesrdquo IOSR Journal of AppliedChemistry vol 8 no 5 pp 1ndash5 2015

[24] K B Modi M K Rangolia M C Chhantbar and H H JJoshi ldquoStudy of infrared spectroscopy and elastic propertiesof fine and coarse grained nickel-cadmium ferritesrdquo Journal ofMaterials Science vol 41 no 22 pp 7308ndash7318 2006

[25] M Rahimi M Eshraghi and P Kameli ldquoStructural and mag-netic characterizations of Cd substituted nickel ferrite nanopar-ticlesrdquo Ceramics International vol 40 no 10 pp 15569ndash155752014

[26] A Sutka and G Mezinskis ldquoSol-gel auto-combustion synthesisof spinel-type ferrite nanomaterialsrdquo Frontiers of MaterialsScience vol 6 no 2 pp 128ndash141 2012

[27] F S Tehrani V Daadmehr A T Rezakhani R H Akbarnejadand S Gholipour ldquoStructural magnetic and optical propertiesof zinc-and copper-substituted nickel ferrite nanocrystalsrdquoJournal of Superconductivity and Novel Magnetism vol 25 no7 pp 2443ndash2455 2012

[28] A V Raut R S Barkule D R Shengule and K M J JadhavldquoSynthesis structural investigation and magnetic properties ofZn2+ substituted cobalt ferrite nanoparticles prepared by thesolndashgel auto-combustion techniquerdquo Journal of Magnetism andMagnetic Materials vol 358-359 pp 87ndash92 2014

[29] P B Belavi G N Chavan L R Naik R Somashekar and R KKotnala ldquoStructural electrical and magnetic properties of cad-mium substituted nickel-copper ferritesrdquo Materials Chemistryand Physics vol 132 no 1 pp 138ndash144 2012

[30] A Mahesh Kumar P Appa Rao M C Varma G S VR K Choudary and K H Rao ldquoCation distribution inCo07Me03Fe2O4(Me = Zn Ni and Mn)rdquo Journal of Modern

Physics vol 2 pp 1083ndash1087 2011[31] ZWuM Okuya and S Kaneko ldquoSpray pyrolysis deposition of

zinc ferrite films frommetal nitrates solutionsrdquoThin Solid Filmsvol 385 no 1-2 pp 109ndash114 2001

[32] A Hajalilou M Hashim H M Kamari and M T MasoudildquoEffects of milling atmosphere and increasing sinteringtemperature on the magnetic properties of nanocrystallineNi036

Zn064

Fe2O4rdquo Journal of Nanomaterials vol 2015 Article

ID 615739 11 pages 2015[33] T J Shinde A B Gadkari and P N Vasambekar ldquoInfluence

of Nd3+ substitution on structural electrical and magneticproperties of nanocrystalline nickel ferritesrdquo Journal of Alloysand Compounds vol 513 pp 80ndash85 2012

[34] S Kumar T J Shinde and P N Vasambekar ldquoStudy ofconduction phenomena in indium substituted MnndashZn nano-ferritesrdquo Journal of Magnetism andMagnetic Materials vol 379pp 179ndash185 2015

[35] G N Chavan P B Belavi L R Naik R K Bammannavar KP Ramesh and S Kumar ldquoElectrical and magnetic properties

of nickel substituted cadmium ferritesrdquo International Journal ofScientific amp Technology Research vol 2 no 12 2013

[36] K V Kumar R Sridhar D Ravinder and K Rama KrishnaldquoStructural properties and electrical conductivity of coppersubstituted nickel nano ferritesrdquo International Journal of AppliedPhysics and Mathematics vol 4 no 2 pp 113ndash117 2014

[37] B A Aldar R K Pinjari and N M Burange ldquoElectric andDielectric behavior of Ni-Co-Cd Ferriterdquo IOSR Journal ofApplied Physics vol 6 no 4 pp 23ndash26 2014

[38] A Ande S Thatikonda R Dachepalli et al ldquoElectrical proper-ties of cadmium substitution in nickel ferritesrdquoWorld Journal ofCondensed Matter Physics vol 2 pp 257ndash266 2012

[39] M B Shelar and V Puri ldquoDielectric loss andmagnetic behaviorof combustion synthesized ferrite-ferroelectric compositesrdquoInternational Journal of Self-Propagating High-Temperature Syn-thesis vol 20 no 2 pp 128ndash133 2011

[40] C G Koops ldquoOn the dispersion of resistivity and dielectricconstant of some semiconductors at audiofrequenciesrdquo PhysicalReview vol 83 no 1 pp 121ndash124 1951

[41] J C Maxwell Electricity and Magnetism Oxford UniversityPress London UK 1973

[42] K W Wagner ldquoZur theorie der unvollkommenen dielektrikardquoAnnalen der Physik vol 345 no 5 pp 817ndash855 1913

[43] K M Batoo S Kumar C G Lee and Alimuddin ldquoInfluenceof Al doping on electrical properties of NindashCd nano ferritesrdquoCurrent Applied Physics vol 9 no 4 pp 826ndash832 2009

[44] A Goldman Modern Ferrite Technology Van Nostrand Rein-hold Company New York NY USA 1990

[45] M H R Khan and A K M Akther Hossain ldquoReen-trant spin glass behavior and large initial permeability ofCo05minus119909

Mn119909Zn05Fe2O4rdquo Journal of Magnetism and Magnetic

Materials vol 324 no 4 pp 550ndash558 2012[46] J M D Coey Rare Earth Permenant Magnetism John Wiley amp

Sons New York NY USA 1996

Submit your manuscripts athttpwwwhindawicom

ScientificaHindawi Publishing Corporationhttpwwwhindawicom Volume 2014

CorrosionInternational Journal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Polymer ScienceInternational Journal of



CeramicsJournal of


CompositesJournal of

NanoparticlesJournal of



International Journal of

Biomaterials


NanoscienceJournal of

TextilesHindawi Publishing Corporation httpwwwhindawicom Volume 2014

Journal of

NanotechnologyHindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Journal of

CrystallographyJournal of


The Scientific World JournalHindawi Publishing Corporation httpwwwhindawicom Volume 2014


CoatingsJournal of

Advances in

Materials Science and EngineeringHindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Smart Materials Research



MetallurgyJournal of


BioMed Research International

MaterialsJournal of


Nano

materials


Journal ofNanomaterials


devices [1 7] multilayer chip inductor (MLCI) [11] highfrequency transformer cores phase shifter resonators com-puters TVs and mobile phones [12ndash16] The spinel structureof NiFe

2O4NPs is constructed by filling the FCC sublattice

of relatively larger oxygen ions and the cation distribution isstrongly dependent on ionic radii as well as concentrationof the substituted divalent metal ions [17] The entire Ni2+cations occupy the [B]-site while the Fe3+ cations distributeequally between (A)-site and [B]-sites Angle AndashOndashB is closerto 180∘ than the angles BndashOndashB and AndashOndashA therefore the ABpair (FendashFe) has a strong antiferromagnetic superexchangeinteraction [18] Postsubstitution site preferences of Cd2+ions are towards the tetrahedral (A) site suggesting thedistribution of cations as

(Cd2+119909Fe3+1minus119909

)

A[Ni2+1minus119909

Fe3+1+119909

]

BO2minus4

(1)

Several possible cation distributions and various magneticorders can be studied at A B1 and B2 sites [19] Nath etal have studied the magnetic orders in Ni-Cd ferrite [6] Inrecent days variety of chemical and physical methods hasbeen employed for the preparation of well-defined magneticNi-Cd ferrite NPs with specific shape and size Rafeek etal have synthesised Ni-Cd NPs by sol-gel autocombustionmethod for the study of the antibacterial effects againstmicroorganism [8 20] Nejati et al have discussed thesuperparamagnetic nature of NiFe

2O4NPs synthesised by

hydrothermal method [11 21] Drmota has discussed theprecipitation in microemulsion method for the controlledsize and morphology of magnetic nanoparticles [22] Sureshet al have prepared Ni-Cd NPs with crystallite size of 15sim23 nm using chemical coprecipitation method [23] Modi etal have studied the pre- and postannealing particle size ofthe Ni-Cd ferrite NPs synthesis by wet-chemical technique[24] Rahimi et al have reported the synthesis of nanoscaleNi1minus119909

Cd119909Fe2O4ferrite powders by sol-gel autocombustion

method using EDTAas a complexion agent [25] In this inves-tigation we have applied sol-gel autocombustion methodfor the production of fine powder of Ni


This preparation technique involves the exothermic andself-sustaining thermally induced anionic redox reaction ofaerogel which is obtained from aqueous solution [26]

2 Experimental Details

21 Synthesis of1198731198941minus11990911986211988911990911986511989021198744 NPs Ni1minus119909Cd119909Fe2O4 spinelferrite NPs (where 119909 = 02 04 06 and 08) were pre-pared successfully by sol-gel autocombustion method usingstoichiometric proportion of 999 pure AR grade ferricnitrate (Fe(NO

3)3sdot9H2O) nickel nitrate (Ni(NO

3)2sdot6H2O)

and cadmium nitrate (Fe(NO3)2sdot4H2O) (gt99) as starting

materials The metal nitrates were dissolved together in thepresence of minimum amount of double distilled deionizedwater Citric acid (C

6H8O7) is significantly used in wet-

chemical methods compared to the other fuels as it ischaracteristically weak organic acid having better complexingability possessing a low ignition temperature (200ndash250∘C)The molar ratio of metal nitrates to citric acid (C

6H8O7) was

taken as 1 3The pH of the solution was maintained at 7 with

the drop by drop addition of ammonia solution Continuousstirring of the mixed nitrate aqueous solution was performedon a magnetic hot-plate stirrer maintaining the temperature90∘CDuring the evaporation stages solution became viscousin colour and later on formed a viscous brown gel Finally astickymass began to bubble for fewminutes in a same beakerThis gel got ignited automatically and burned with a glowingflint The decomposition process would not stop before thewhole citrate complex was consumed As a yield productof this reaction fluffy loose powder of brown colouredash could be termed as Ni

1minus119909Cd119909Fe2O4presintered ferrite

The prepared samples were dried and annealed at 800∘Cfor 12 h after thermogravimetric analysis (TGA) Some partof the annealed Ni

1minus119909Cd119909Fe2O4NPs was granulated with

the addition of saturated PVA solution (polyvinyl alcohol(C2H4O)119909) as a binder These granulated NPs were used to

prepare disc shaped pellets of 10mm diameter and 3mmthickness using the hydraulic press by applying pressure of5 tonscm2 for 5min in a stainless steel die

3 Results and Discussion

31 X-Ray Diffraction Study of 1198731198941minus11990911986211988911990911986511989021198744 NPs X-raydiffraction patterns of Ni

1minus119909Cd119909Fe2O4NPs were recorded

with the X-ray diffractometer (Philips) XRD of all sampleswere recorded in the 2120579 range of 20ndash80∘ withCu-K120572 radiation(120582 = 15405 au) at room temperature All the peaks wereidentified by comparing the ldquo119889rdquo spacing with that of JCPDSdata of NiFe

2O4and CdFe

2O4in order to confirm the

crystalline phases present The major lattice planes (220)(311) (400) (422) (511) and (440) in Figure 1 confirm theformation of single phase Ni

1minus119909Cd119909Fe2O4with a face centred

cubic spinel structure space group Fd3mAccordinglyminorlattice planes (222) (533) (622) and (444) in XRD patterngave supporting agreement about the powder diffractionof the spinel cubic JCPDS [27] Cation distribution wasestimated from the comparison between observed intensityratios (119868obs) and calculated intensity ratios (119868cal) by followingthe Bertaut method [12] The values of structural parameterslike peak intensity ratios hopping length (119871A 119871B) and bondlength (119877A 119877B) are depicted in Table 1 Lattice constant (119886)of Ni1minus119909

Cd119909Fe2O4NPs (Table 1) was determined from X-ray

data analysis with an accuracy of plusmn0002gt using the formula[28]

119886 = 119889radic(ℎ2+ 1198962+ 1198972) (2)

where 119886 is a lattice constant (ℎ 119896 119897) represents the Millerindices 120582 is a wavelength of X-rays and 120579 is the glancingangle It can be noticed from Figure 2 that the value of latticeparameter increased with the increase in Cd2+ content [29]from 8350 A to 8491 A (plusmn0002gt) which is attributed to thelarger ionic radius of Cd2+ (097 A) ions than that of Ni2+(078 A) ions obeyingVegardrsquos law [12] Crystallite size (119905) wasdetermined by using the Scherrer formula [30]

119905 =

089120582

120573 cos 120579 (3)



Cd (119909) Ni1minus119909

Cd119909Fe2O4

119868(220)

119868(440)

119868(400)

119868(422)

119868(400)

119868(440)


02 (Cd02Fe08)A[Ni

08Fe12]B 0756 0872 131 193 0351 0578 3615 2951 1894 2038

04 (Cd04Fe06)A [Ni

06Fe14]B 0912 0776 074 109 0250 0464 3621 2956 1897 2041

06 (Cd06Fe04)A [Ni

04Fe16]B 1099 0964 043 113 0174 0397 3633 2966 1904 2048

08 (Cd08Fe02)A [Ni

02Fe18]B 1261 1226 0114 0571 025 067 3676 3001 1926 2072


Cd119909Fe2O4

NPs


119891(eV) Δ119864 plusmn 119864

119875minus 119864119865(eV) 119879

119862

∘C02 8350 4689 5593 3920 038 034 004 86004 8363 4870 5811 4029 021 018 003 79706 8390 5530 5995 3952 04 027 015 76608 8491 5840 6017 3817 034 028 006 566

Inte

nsity

(au

)

02 04

06

(622

)(5

33)

(444

)

08

(220

) (311

)(2

22) (400

)

(422

) (511

)

(440

)

30 40 50 60 70 80202120579 (deg)


Cd119909Fe2O4NPs for 119909 =

02 04 06 and 08




aEP

EP

EF

EF

015

018

021

024

027

030

033

036

039

042

EP

-EF

(eV

)


834

836

838

840

842

844

846

848

850

Latti

ce co

nsta

nt a

(Aring)


119865in


Cd119909Fe2O4

NPs


119889X =

8119872

(119873A1198863)

(4)


119875 = (

119889X minus 119889B119889X

) times 100 (5)














behaviour






120588 = 120588119900exp(Δ119864119870B119879) (6)



119865) with




1minus119909Cd119909Fe2O4NPs [36]









02

log 120588

(Ωcm

)

16

20

24

28

32

12 13 14 15 1611A

(a) 04

log 120588

(Ωcm

)

46

48

50

52

54

56

13 14 15 1612A

(b)

06

log 120588

(Ωcm

)

08

12

16

20

24

12 13 14 15 16111000T (K)

(c) 08

log 120588

(Ωcm

)

08

10

12

14

16

13 14 15 16121000T (K)

(d)


Cd119909Fe2O4NPs for 119909 = 02 04 06 and 08






119904)


119888) and square-



Cd119909Fe2O4NPs


119873

B is given by

119899119873

B (119883) = 119872B (119883) minus119872A (119883) (8)





119905and 119870





Cd119909Fe2O4NPs

Cd (119909) 1205921(cmminus1) 120592

2(cmminus1) 119870

119905times 105 (dynecm) 119870


119904(emug) 119867


02 57940 46978 13355 17179 9703 13 258 004 58334 47512 13592 20347 9422 19 257 29∘301015840

06 57919 47766 13669 22950 6611 32 190 53∘431015840


02 04

06 08

times104

120576998400


20 40 60 80 1000Frequency


Cd119909Fe2O4NPs

0204

0608

tan 120575

0123456789

10

25 30 35 40 45 50 55 60 6520log F


Cd119909Fe2O4NPs


120583B = 119872B cos120572Y-K minus119872A (9)

0204

0608

minus5000

minus4000

minus3000

minus2000

minus1000

0

1000

2000

3000

4000

5000

Mag

netiz

atio

n (e

mu

gm)


minus20

0

20

Mag

netiz

atio

n (e

mu

gm)


minus2000

minus3000

minus4000

minus5000

Mag

netiz

atio

n (e

mu

gm)


Applied field (Oe)


Cd119909Fe2O4NPs


119904) from 9422 to




119888= 211989611205830119896119872119904 For 119909= 02ndash06




4 Conclusions

Ni1minus119909





119862




119904) from 9422 to

1373 (emug)

Highlights

(i) Ni1minus119909






substitution



Acknowledgment


References


























325 pp 144ndash146 2013
















Zn064



























CeramicsJournal of







Biomaterials




Journal of


Journal of





CoatingsJournal of

Advances in








MaterialsJournal of


Nano

materials





Cd (119909) Ni1minus119909

Cd119909Fe2O4

119868(220)

119868(440)

119868(400)

119868(422)

119868(400)

119868(440)


02 (Cd02Fe08)A[Ni

08Fe12]B 0756 0872 131 193 0351 0578 3615 2951 1894 2038

04 (Cd04Fe06)A [Ni

06Fe14]B 0912 0776 074 109 0250 0464 3621 2956 1897 2041

06 (Cd06Fe04)A [Ni

04Fe16]B 1099 0964 043 113 0174 0397 3633 2966 1904 2048

08 (Cd08Fe02)A [Ni

02Fe18]B 1261 1226 0114 0571 025 067 3676 3001 1926 2072


Cd119909Fe2O4

NPs


119891(eV) Δ119864 plusmn 119864

119875minus 119864119865(eV) 119879

119862

∘C02 8350 4689 5593 3920 038 034 004 86004 8363 4870 5811 4029 021 018 003 79706 8390 5530 5995 3952 04 027 015 76608 8491 5840 6017 3817 034 028 006 566

Inte

nsity

(au

)

02 04

06

(622

)(5

33)

(444

)

08

(220

) (311

)(2

22) (400

)

(422

) (511

)

(440

)

30 40 50 60 70 80202120579 (deg)


Cd119909Fe2O4NPs for 119909 =

02 04 06 and 08




aEP

EP

EF

EF

015

018

021

024

027

030

033

036

039

042

EP

-EF

(eV

)


834

836

838

840

842

844

846

848

850

Latti

ce co

nsta

nt a

(Aring)


119865in


Cd119909Fe2O4

NPs


119889X =

8119872

(119873A1198863)

(4)


119875 = (

119889X minus 119889B119889X

) times 100 (5)














behaviour






120588 = 120588119900exp(Δ119864119870B119879) (6)



119865) with




1minus119909Cd119909Fe2O4NPs [36]









02

log 120588

(Ωcm

)

16

20

24

28

32

12 13 14 15 1611A

(a) 04

log 120588

(Ωcm

)

46

48

50

52

54

56

13 14 15 1612A

(b)

06

log 120588

(Ωcm

)

08

12

16

20

24

12 13 14 15 16111000T (K)

(c) 08

log 120588

(Ωcm

)

08

10

12

14

16

13 14 15 16121000T (K)

(d)


Cd119909Fe2O4NPs for 119909 = 02 04 06 and 08






119904)


119888) and square-



Cd119909Fe2O4NPs


119873

B is given by

119899119873

B (119883) = 119872B (119883) minus119872A (119883) (8)





119905and 119870





Cd119909Fe2O4NPs

Cd (119909) 1205921(cmminus1) 120592

2(cmminus1) 119870

119905times 105 (dynecm) 119870


119904(emug) 119867


02 57940 46978 13355 17179 9703 13 258 004 58334 47512 13592 20347 9422 19 257 29∘301015840

06 57919 47766 13669 22950 6611 32 190 53∘431015840


02 04

06 08

times104

120576998400


20 40 60 80 1000Frequency


Cd119909Fe2O4NPs

0204

0608

tan 120575

0123456789

10

25 30 35 40 45 50 55 60 6520log F


Cd119909Fe2O4NPs


120583B = 119872B cos120572Y-K minus119872A (9)

0204

0608

minus5000

minus4000

minus3000

minus2000

minus1000

0

1000

2000

3000

4000

5000

Mag

netiz

atio

n (e

mu

gm)


minus20

0

20

Mag

netiz

atio

n (e

mu

gm)


minus2000

minus3000

minus4000

minus5000

Mag

netiz

atio

n (e

mu

gm)


Applied field (Oe)


Cd119909Fe2O4NPs


119904) from 9422 to




119888= 211989611205830119896119872119904 For 119909= 02ndash06




4 Conclusions

Ni1minus119909





119862




119904) from 9422 to

1373 (emug)

Highlights

(i) Ni1minus119909






substitution



Acknowledgment


References


























325 pp 144ndash146 2013
















Zn064



























CeramicsJournal of







Biomaterials




Journal of


Journal of





CoatingsJournal of

Advances in








MaterialsJournal of


Nano

materials
















behaviour






120588 = 120588119900exp(Δ119864119870B119879) (6)



119865) with




1minus119909Cd119909Fe2O4NPs [36]









02

log 120588

(Ωcm

)

16

20

24

28

32

12 13 14 15 1611A

(a) 04

log 120588

(Ωcm

)

46

48

50

52

54

56

13 14 15 1612A

(b)

06

log 120588

(Ωcm

)

08

12

16

20

24

12 13 14 15 16111000T (K)

(c) 08

log 120588

(Ωcm

)

08

10

12

14

16

13 14 15 16121000T (K)

(d)


Cd119909Fe2O4NPs for 119909 = 02 04 06 and 08






119904)


119888) and square-



Cd119909Fe2O4NPs


119873

B is given by

119899119873

B (119883) = 119872B (119883) minus119872A (119883) (8)





119905and 119870





Cd119909Fe2O4NPs

Cd (119909) 1205921(cmminus1) 120592

2(cmminus1) 119870

119905times 105 (dynecm) 119870


119904(emug) 119867


02 57940 46978 13355 17179 9703 13 258 004 58334 47512 13592 20347 9422 19 257 29∘301015840

06 57919 47766 13669 22950 6611 32 190 53∘431015840


02 04

06 08

times104

120576998400


20 40 60 80 1000Frequency


Cd119909Fe2O4NPs

0204

0608

tan 120575

0123456789

10

25 30 35 40 45 50 55 60 6520log F


Cd119909Fe2O4NPs


120583B = 119872B cos120572Y-K minus119872A (9)

0204

0608

minus5000

minus4000

minus3000

minus2000

minus1000

0

1000

2000

3000

4000

5000

Mag

netiz

atio

n (e

mu

gm)


minus20

0

20

Mag

netiz

atio

n (e

mu

gm)


minus2000

minus3000

minus4000

minus5000

Mag

netiz

atio

n (e

mu

gm)


Applied field (Oe)


Cd119909Fe2O4NPs


119904) from 9422 to




119888= 211989611205830119896119872119904 For 119909= 02ndash06




4 Conclusions

Ni1minus119909





119862




119904) from 9422 to

1373 (emug)

Highlights

(i) Ni1minus119909






substitution



Acknowledgment


References


























325 pp 144ndash146 2013
















Zn064



























CeramicsJournal of







Biomaterials




Journal of


Journal of





CoatingsJournal of

Advances in








MaterialsJournal of


Nano

materials




02

log 120588

(Ωcm

)

16

20

24

28

32

12 13 14 15 1611A

(a) 04

log 120588

(Ωcm

)

46

48

50

52

54

56

13 14 15 1612A

(b)

06

log 120588

(Ωcm

)

08

12

16

20

24

12 13 14 15 16111000T (K)

(c) 08

log 120588

(Ωcm

)

08

10

12

14

16

13 14 15 16121000T (K)

(d)


Cd119909Fe2O4NPs for 119909 = 02 04 06 and 08






119904)


119888) and square-



Cd119909Fe2O4NPs


119873

B is given by

119899119873

B (119883) = 119872B (119883) minus119872A (119883) (8)





119905and 119870





Cd119909Fe2O4NPs

Cd (119909) 1205921(cmminus1) 120592

2(cmminus1) 119870

119905times 105 (dynecm) 119870


119904(emug) 119867


02 57940 46978 13355 17179 9703 13 258 004 58334 47512 13592 20347 9422 19 257 29∘301015840

06 57919 47766 13669 22950 6611 32 190 53∘431015840


02 04

06 08

times104

120576998400


20 40 60 80 1000Frequency


Cd119909Fe2O4NPs

0204

0608

tan 120575

0123456789

10

25 30 35 40 45 50 55 60 6520log F


Cd119909Fe2O4NPs


120583B = 119872B cos120572Y-K minus119872A (9)

0204

0608

minus5000

minus4000

minus3000

minus2000

minus1000

0

1000

2000

3000

4000

5000

Mag

netiz

atio

n (e

mu

gm)


minus20

0

20

Mag

netiz

atio

n (e

mu

gm)


minus2000

minus3000

minus4000

minus5000

Mag

netiz

atio

n (e

mu

gm)


Applied field (Oe)


Cd119909Fe2O4NPs


119904) from 9422 to




119888= 211989611205830119896119872119904 For 119909= 02ndash06




4 Conclusions

Ni1minus119909





119862




119904) from 9422 to

1373 (emug)

Highlights

(i) Ni1minus119909






substitution



Acknowledgment


References


























325 pp 144ndash146 2013
















Zn064



























CeramicsJournal of







Biomaterials




Journal of


Journal of





CoatingsJournal of

Advances in








MaterialsJournal of


Nano

materials






119905and 119870





Cd119909Fe2O4NPs

Cd (119909) 1205921(cmminus1) 120592

2(cmminus1) 119870

119905times 105 (dynecm) 119870


119904(emug) 119867


02 57940 46978 13355 17179 9703 13 258 004 58334 47512 13592 20347 9422 19 257 29∘301015840

06 57919 47766 13669 22950 6611 32 190 53∘431015840


02 04

06 08

times104

120576998400


20 40 60 80 1000Frequency


Cd119909Fe2O4NPs

0204

0608

tan 120575

0123456789

10

25 30 35 40 45 50 55 60 6520log F


Cd119909Fe2O4NPs


120583B = 119872B cos120572Y-K minus119872A (9)

0204

0608

minus5000

minus4000

minus3000

minus2000

minus1000

0

1000

2000

3000

4000

5000

Mag

netiz

atio

n (e

mu

gm)


minus20

0

20

Mag

netiz

atio

n (e

mu

gm)


minus2000

minus3000

minus4000

minus5000

Mag

netiz

atio

n (e

mu

gm)


Applied field (Oe)


Cd119909Fe2O4NPs


119904) from 9422 to




119888= 211989611205830119896119872119904 For 119909= 02ndash06




4 Conclusions

Ni1minus119909





119862




119904) from 9422 to

1373 (emug)

Highlights

(i) Ni1minus119909






substitution



Acknowledgment


References


























325 pp 144ndash146 2013
















Zn064



























CeramicsJournal of







Biomaterials




Journal of


Journal of





CoatingsJournal of

Advances in








MaterialsJournal of


Nano

materials





119862




119904) from 9422 to

1373 (emug)

Highlights

(i) Ni1minus119909






substitution



Acknowledgment


References


























325 pp 144ndash146 2013
















Zn064



























CeramicsJournal of







Biomaterials




Journal of


Journal of





CoatingsJournal of

Advances in








MaterialsJournal of


Nano

materials


















Zn064



























CeramicsJournal of







Biomaterials




Journal of


Journal of





CoatingsJournal of

Advances in








MaterialsJournal of


Nano

materials










CeramicsJournal of







Biomaterials




Journal of


Journal of





CoatingsJournal of

Advances in








MaterialsJournal of


Nano

materials



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