Crystal transformation of 2D tungstic acid H2WO4 to WO3 for enhanced photocatalytic water oxidation

JOURNAL OF COLLOID AND INTERFACE SCIENCE

卷:514

Article

Ke, Jun^1,2  Zhou, Hongru¹  Liu, Jie^2,3  Duan, Xiaoguang²  Zhang, Huayang²  Liu, Shaomin²  Wang, Shaobin² 

[1] Wuhan Inst Technol, Sch Chem & Environm Engn, Wuhan 430205, Hubei, Peoples R China

[2] Curtin Univ, Dept Chem Engn, GPO Box U1987, Perth, WA 6845, Australia

[3] North China Elect Power Univ, Sch Environm Sci & Engn, Baoding 071003, Peoples R China

关键词: Photocatalytic water oxidation;    2D materials;    Crystal transformation;    WO3;   

DOI  :  10.1016/j.jcis.2017.12.066

来源: Elsevier

【 摘 要 】

New photocatalytic materials for stable reduction and/or oxidization of water by harvesting a wider range of visible light are indispensable to achieve high practical efficiency in artificial photosynthesis. In this work, we prepared 2D WO3 center dot H2O and WO3 nanosheets by a one-pot hydrothermal method and sequent calcination, focusing on the effects of crystal transformation on band structure and photocatalytic performance for photocatalytic water oxidation in the presence of electron acceptors (Ag+) under simulated solar light irradiation. The as-prepared WO3 nanosheets exhibit enhanced rate of photocatalytic water oxidation, which is 6.3 and 3.6 times higher than that of WO3 center dot H2O nanosheets and commercial WO3, respectively. It is demonstrated that the releasing of water molecules in the crystal phase of tungstic acid results in transformation of the crystal phase from orthorhombic WO3 center dot H2O to monoclinic WO3, significantly improving the activity of photocatalytic water oxidation in the presence of Ag+ because the shift-up of conduction band of WO3 matches well with the electrode potential of Ag+/Ag(s), leading to efficient separation of photoinduced electrons and holes in pure WO3 nanosheets. (C) 2017 Elsevier Inc. All rights reserved.

【 授权许可】

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