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Preparation and characterization of SnO2

nanoparticle of enhanced thermal stability: The effect of phosphoric acid treatment on SnO2 · nH2O

Laszlo Korosi, Szilvia Papp , Vera Meynen, Pegie Cool, Etienne F. Vansant , Imre DekanyColloids and Surfaces A: Physicochem. Eng. Aspects 268 (2005) 147–154

Sameh HamzawyMESC9

Outline

Introduction

Experiment

Results and discussion

Conclusion

Enhancement the thermal stability of tin oxide hydrate ( SnO2.H20) by the phosphoric acid treatment.

Tin dioxide has many motivated application, such as n-type semiconductor, DSSC, Li-batteries, photocatalysts,…etc.

Analyze the structural and surface properties of phosphorus containing SnO2 using different techniques.

Introduction

Preparation of a reference sample of tin hydrogen phosphate (Sn(HPO4)2 · nH2O).

The preparation of P-SnO2 was performed in two stages:

2- (SnO2.H20 ) was treated with different concentrations phosphoric acid solution to prepare samples with different (P:Sn ) molar ratios.

Experiment

1- Tin oxide hydrate was prepared by the hydrolysis of tin(IV) chloride.

Wei

ght l

oss(

%)

Temperature ( ᴼC)

Fig.1: Thermogravimetric curves of SnO2, Sn(HPO4)2 and P-SnO2/3.4 dried at 80◦C.

The TG curve shows the total weight loss for :

Sn(HPO4)2 15% up to 800 ∼◦C

Sn(HPO4)2 · nH2O → Sn(HPO4)2 + nH2O

Sn(HPO4)2 → SnP2O7 + H2O

P-SnO2/3.4 11%. up to 800 ◦C ∼

Results and discussion

SnO2 14% up to 800 ᴼC.∼

Fig. 3. XRD patterns of SnO2 with different phosphate contents after 800 ◦C calcination.

Fig. 2. DRIFT spectra of (a) different P- SnO2 after drying at 80 ◦C.

Inte

nsity

Fig.4(b)P-SnO2/1.1 sample at different calcined temperatures.

Fig. 4(a) XRD patterns of (a) pure SnO2 at different calcined temperatures.

Inte

nsity

Fig.5. XRD patterns of different phosphate content tin dioxide and cubic tin phosphate calcined at 1000◦C.

Fig.6. UV–vis diffuse reflectance spectra of different P- SnO2 samples, dried at 80◦C.

Fig.7: Schematic illustration of the effect of phosphoric acid and heat treatment on SnO2 · nH2O.

SnO2 of enhanced thermal stability was prepared.

The phosphate coverage of tin oxide hydrate particles can be controlled via the phosphoric acid concentration.

The extent of sintering of SnO2 is reduced and it is proportional to phosphoric acid concentration,

At low phosphate content modification of SnO2 has high thermal stability in addition to the photocatalytic activity.

Conclusion

Thank you for your attention

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