open access

https://hdl.handle.net/2115/84730

Enhancement of UV-responsive photocatalysts aided by visible-light responsive photocatalysts : Role of WO3 for H2 evolution on CuCl

英語

Charge carrier dynamics

2020-04

Applied Catalysis B: Environmental

263

118333

WO3 is one of the most popular materials for visible-light photocatalysts. However, its conduction band minimum is too low for water reduction. Here, we found that WO3 can assist water reduction by using visible light in a CuCl2 aqueous solution. Photoirradiation of WO3 in CuCl2 reduces Cu2+ to form indissoluble CuCl adducts, and as-produced CuCl/WO3 was active for H2 evolution under UV-light. This composite has very low reactivity under visible light (>400 nm), but visible-light assisted H2 evolution was observed with simultaneous irradiation with UV light: the activity was increased ∼1.7 fold. Transient absorption measurements revealed that Z-schematic recombination initially takes place between photogenerated electrons in WO3 and holes in CuCl. As a result, the lifetime of electrons in CuCl was increased, enhancing H2 evolution. These results demonstrate that inactive narrow-band gap materials can be used to enhance the activity of wide-band gap materials under sunlight illumination.

学術雑誌論文

Accepted Manuscript

Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International

© 2020. This manuscript version is made available under the CC-BY-NC-ND 4.0 license https://creativecommons.org/licenses/by-nc-nd/4.0/

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