Influence of alkoxide structures on formation of TiO2/WO3 heterojunctions for photocatalytic decomposition of organic compounds

- TiO2/WO3 heterostructured photocatalyst by a sol-gel spin coating method.
- TiO2/WO3 photocatalyst films from three types of TiO2 precursors.
- Different portions of Ti-O-W heterojunctions from different types of TiO2 precursors.
- Improved photodecomposition of organic compounds with well scattered WO3 crystals.

Reducing recombination and lowering band gap can be achieved with heterostructured photocatalysts, and the TiO2 photocatalyst film coupled with WO3 component maintains its advantageous characteristics. In order to investigate the effect of molecular structures on heterojunction formation, the three types of TiO2 precursors were used to make TiO2/WO3 heterojunction. The TiO2/WO3 composite films with high transmittance were successfully fabricated by the sol-gel spin coating method. Formation of Ti-O-W linkage was preferable from the precursor with small steric hindrance, and it was confirmed with the well scattered WO3 components in TiO2 crystal matrix and also with reduced TiO2 crystal size. High portion of Ti-O-W bond resulted in the most effective photocatalytic activity. Therefore, it is important to use a proper precursor to improve photodecomposition efficiency in manufacturing the heterostructured photocatalysts.

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