摘要
The bottleneck for water splitting to generate hydrogen fuel is the sluggish oxidation of water. Even though the monoclinic-BiVO4 (m-BiVO4)-based heterostructure has been widely applied for water oxidation, carrier recombination on dual surfaces of the m-BiVO4 component have not been fully resolved by a single heterojunction. Inspired by natural photosynthesis, we established an m-BiVO4/carbon nitride (C3N4) Z-scheme heterostructure based on the m-BiVO4/reduced graphene oxide (rGO) Mott-Schottky heterostructure, constructing the face-contact C3N4/m-BiVO4/rGO (CNBG) ternary composite to remove excessive surface recombination during water oxidation. The rGO can accumulate photogenerated electrons from m-BiVO4 through a high conductivity region over the heterointerface, with the electrons then prone to diffuse along a highly conductive carbon network. In an internal electric field at the heterointerface of m-BiVO4/C3N4, the low-energy electrons and holes are rapidly consumed under irradiation. Therefore, spatial separation of electron-hole pairs occurs, and strong redox potentials are maintained by the Z-scheme electron transfer. These advantages endow the CNBG ternary composite with over 193% growth in O2 yield, and a remarkable rise in ·OH and ·O2− radicals, compared to the m-BiVO4/rGO binary composite. This work shows a novel perspective for rationally integrating Z-scheme and Mott-Schottky heterostructures in the water oxidation reaction.
源语言 | 英语 |
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页(从-至) | 3386-3395 |
页数 | 10 |
期刊 | Nanoscale Advances |
卷 | 5 |
期 | 12 |
DOI | |
出版状态 | 已出版 - 10 5月 2023 |