Abstract
InTaO4 is an efficient visible-light photocatalyst, which used to be synthesized by solid-state fusion at over 1100 °C. However, irregular morphology and severe agglomeration of particles were acquired due to nonuniform fusion of solid precursors. In this study, InTaO4 was synthesized by two sol-gel routes, the thermal hydrolysis and esterification methods. The precursors were indium (III) nitrate pentahydrate [In(NO3)3] and tantalum(V) butoxide [Ta(OC4H9)5] dissolved in solutions. The InTaO4 powders with a uniform grain size of 17.7 nm were successfully synthesized using the esterification method at a calcination temperature of 950 °C. A uniform InTaO4 thin film nearly 40 nm thick formed on an optical fiber at 1100 °C using the sol prepared by the esterification method. For the first time, InTaO4 was evaluated by the photocatalytic activity of CO2 photo reduction, which was conducted in aqueous solution under visible light irradiation. Cocatalyst NiO was loaded on the surface of InTaO4 to further enhance the methanol yield. The methanol yields of NiO/InTaO4 by esterification method were significantly higher than those by solid-state fusion. The esterification method provided homogeneous mixing of Ta(OC4H9)5 and In(NO3)3, resulting in nano-sized InTaO4 with uniform crystallinity and superior photocatalytic activity.
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K. Honda A. Fujishima: Electrochemical photolysis of water at a semiconductor electrode. Nature 238, 37 1972
S. Kuwabata, K. Nishida, R. Tsuda, H. Inoue H. Yoneyama: Photochemical reduction of carbon dioxide to methanol using ZnS microcrystallite as a photocatalyst in the presence of methanol dehydrogenase. J. Electrochem. Soc. 141, 1498 1994
J.C.S. Wu, H-M. Lin C-L. Lai: Photo reduction of CO2 to methanol using optical-fiber photo reactor. Appl. Catal., A: Gen. 296, 194 2005
J. Ye, Z. Zou, H. Arakawa, M. Oshikiri, M. Shimoda, A. Matsushita T. Shishido: Correlation of crystal and electronic structures with photophysical properties of water splitting photocatalysts InMO4 (M = V5+, Nb5+, Ta5+). J. Photochem. Photobio., A: Chem. 148, 79 2002
Z. Zou, J. Ye H. Arakawa: Photophysical and photocatalytic properties of InMO4 (M = V5+, Nb5+, Ta5+) under visible light irradiation. Mat. Res. Bull. 36, 1185 2001
Z. Zou, J. Ye H. Arakawa: Structural properties of InNbO4 and InTaO4: Correlation with photocatalytic and photophysical properties. Chem. Phys. Lett. 332, 271 2000
I-H. Tseng, W-C. Chang J.C.S. Wu: Photoreduction of CO2 using sol-gel-derived titania and titania-supported copper catalysts. Appl. Catal., B: Environ. 37, 37 2002
JCPDS No. 25-0391. International Center for Data Diffraction Newton Square, PA (JCPDS-ICDD PDF-2 Database): version 2.15, Academia Sinica 1987
M.R. Hoffmann, S.T. Martin, W. Choi D.W. Bahnemannt: Pristine points of zero charge of gallium and indium oxides. J. Colloid Interface Sci. 238, 225 2001
M. Marezio: Refinement of the crystal structure of In2O3 at two wavelengths. Acta Crystallogr. 20, 723 1966
G. Vlaic, D. Andreatta P.E. Colavita: Characterisation of heterogeneous catalysts by EXAFS. Catal. Today 41, 261 1998
Z. Zou, J. Ye, K. Sayama H. Arakawa: Direct splitting of water under visible light irradiation with an oxide semiconductor photocatalyst. Nature 414, 625 2001
Acknowledgment
The authors would like to acknowledge the National Science Council of Taiwan for financial supporting of this research under Contract No. NSC 95-EPA-Z-002-007.
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Chen, HC., Chou, HC., Wu, J.C. et al. Sol-gel prepared InTaO4 and its photocatalytic characteristics. Journal of Materials Research 23, 1364–1370 (2008). https://doi.org/10.1557/JMR.2008.0172
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DOI: https://doi.org/10.1557/JMR.2008.0172