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论文类型：期刊论文

发表时间：2020-05-26

发表刊物：ACS APPLIED ENERGY MATERIALS

收录刊物：SCIE

卷号：3

期号：5

页面范围：5083-5094

ISSN号：2574-0962

关键字：CO2 reduction; direct Z-scheme; oriented charge transfer; interfacial defect; DFT calculation

摘要：Constructing efficient photocatalysts for CO2 conversion and synthesis of valuable chemical fuels has been one of the most promising strategies and challenge for both energy crisis and greenhouse gas control. In this study, an interfacial defect in the Cobased spinel/carbon nitride direct Z-scheme heterojunction (Co3O4/CNS) with ultrahigh charge transfer efficiency was successfully constructed by in situ electrostatic assembly between g-C3N4 nanosheets and a hollow spherical Co3O4. Compared to pure g-C3N4 nanosheets, the constructed heterojunction Co3O4/CNS-10% shows a highly advanced photocatalytic capability with approximately 11.5 and 6.4 times in the CO evolution rate (13.31 mu mol.g(-1).h(-1)) and CH4 generation rate (3.17 mu mol.g(-1).h(-1)), respectively. Additionally, both experimental observations and density functional theory calculations reveal that the oxygen vacancies could form spontaneously in the interface, which play a great role in not only driving oriented interface charge transfer through acting as interface charge recombination centers but also improving CO2 molecule adsorption and activation in a sense. This work would not only provides deep insights into the heterojunction construction for highly photocatalytic performance promotion but also emphasizes the importance of interfacial defect engineering in effectively controllable interface charge transfer.