Preparation, characterization and photocatalytic behavior of WO₃-TiO₂/Nb₂O₅ catalysts

Abstract

TiO₂/Nb₂O₅ photocatalyst loaded with WO₃ (WO₃-TiO₂/Nb₂O₅) was prepared by a modified hydrolysis process, and characterized by X-ray diffractometry, transmission electron microscopy, Raman spectra and UV-Vis diffuse refraction spectroscopy. The photocatalytic activity of WO₃-TiO₂/Nb₂O₅ was investigated by employing splitting of water for O₂ evolution. The results indicate that WO₃ loading can pronouncedly improve the photocatalytic activity of TiO₂/Nb₂O₅ by using Fe³⁺ as an electron acceptor under UV irradiation. The optimum molar fraction of the loaded WO₃ is 2%, and the largest speed of O₂ evolution for 2% WO₃-TiO₂/Nb₂O₅ catalyst is 151.8 µmol/(L·h).

Keywords

photocatalysis / load / oxygen evolution / rutile TiO₂ / Nb₂O₅ / WO₃

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