Tailored defects on a semiconductor surface can provide active catalytic sites and effectively tune the electronic structure for suitable optical properties. Herein, we report that surface modification of WO 3 with a disordered layer enables the photochemical hydrogen production from water. A simple room temperature solution process with lithium-ethylenediamine (Li-EDA) alters the surface of WO 3 with localized defects that form a thin disordered layer. Both structural and optical characterization reveal that such a disordered layer induces an upshift in the Fermi level and the elevation of the conduction band of WO 3 above the hydrogen reduction potential. Using an alkaline sacrificial agent, Li-EDA treated WO 3 shows a co-catalyst-free photochemical hydrogen evolution rate of 94.2 μmol g -1 h -1 under simulated sunlight. To the best of our knowledge, this is the first example of using WO 3 as a direct photocatalyst for hydrogen generation from water via simple surface defect engineering.
Bibliographical noteFunding Information:
This work was supported by the Innovation and Technology Commission, The Hong Kong Polytechnic University (Grant No. G-YBSZ and 1-BE0Y), and the National Natural Science Foundation of China (Grants No. 21701135). L. W. acknowledges the award of a postdoctoral fellowship by The Hong Kong Polytechnic University. K. Y. W. acknowledges the support by the Patrick S. C. Poon endowed professorship.
© 2019 The Royal Society of Chemistry.
All Science Journal Classification (ASJC) codes
- Renewable Energy, Sustainability and the Environment
- Materials Science(all)