NiO-TiO2 p-n Heterojunction for Solar Hydrogen Generation

Catalysts

Zhangxin Chen¹  Heng Zhao¹  Jinguang Hu¹  Dewen Zheng²  Shanyu Wang² 

[1] Department of Chemical and Petroleum Engineering, University of Calgary, 2500 University Drive, NW, Calgary, AB T2N 1N4, Canada;Research Institute of Petroleum Exploration and Development (RIPED), CNPC, Beijing 100083, China;

关键词: hydrogen production;    photocatalysis;    p-n heterojunction;    NiO;    TiO₂;   

DOI  :  10.3390/catal11121427

来源: DOAJ

【 摘 要 】

Photocatalytic water splitting for hydrogen production has been widely recognized as a promising strategy for relieving the pressure from energy crisis and environmental pollution. However, current efficiency for photocatalytic hydrogen generation has been limited due to a low separation of photogenerated electrons and holes. p-n heterojunction with a built-in electric field emerges as an efficient strategy for photocatalyst design to boost hydrogen evolution activities due to a spontaneous charge separation. In this work, we investigated the effect of different preparation methods on photocatalytic hydrogen production over NiO-TiO₂ composites. The results demonstrated that a uniform distribution of NiO on a surface of TiO₂ with an intimate interfacial interaction was formed by a sol-gel method, while direct calcination tended to form aggregation of NiO, thus leading to an uneven p-n heterojunction structure within a photocatalyst. NiO-TiO₂ composites fabricated by different methods showed enhanced hydrogen production (23.5 ± 1.2, 20.4 ± 1.0 and 8.8 ± 0.7 mmolh⁻¹g⁻¹ for S1-20%, S2-20% and S3-10%, respectively) as compared with pristine TiO₂ (6.6 ± 0.7 mmolh⁻¹g⁻¹) and NiO (2.1 ± 0.2 mmolh⁻¹g⁻¹). The current work demonstrates a good example to improve photocatalytic hydrogen production by finely designing p-n heterojunction photocatalysts.

【 授权许可】

Unknown