氧空位增强光催化还原CO2性能方面的研究进展

利用太阳能和半导体光催化剂,将CO₂光催化还原转变成碳氢燃料,是缓解温室效应、全球变暖、环境污染和能源危机等一系列问题的理想途径。 本文对氧空位增强的光催化还原CO₂反应机理进行归纳,并分别针对还原产物为C1和C2组分的光催化体系进行概括总结。 作为CO₂光催化还原过程的第一步,CO₂捕获光催化剂导带上的电子生成CO2·-是反应的速控步骤。 氧空位的引入及其带来的金属配位不饱和点,利于CO₂捕获电子生成CO2·-,进而促进CO₂光催化还原过程。 最后,提出当前氧空位增强光催化还原CO₂过程仍然存在的问题,且对发展前景进行展望。

Research Progress in Photocatalytic Reduction of CO2 Enhanced by Oxygen Vacancy

The photocatalytic reduction reactions can directly convert carbon dioxide(CO 2)into hydrocarbon solar fuels utilizing the endless solar energy and semiconductor photocatalysts,which can solve the greenhouse effect,global warming,environmental pollution,and energy crisis,therefore it has become the ideal way nowadays.The mechanism of photocatalytic reduction of CO2 enhanced by oxygen vacancy and the photocatalytic systems with C1 and C2 components as reduction products were summarized in this paper.The first step in the CO2 photoreduction(i.e.the formation of CO2^·- anionic radical by capturing an electron from the conduction band of a photocatalyst)was considered to be the rate-limiting step.The introduction of oxygen vacancy and induced coordinately unsaturated metal atoms sites could strengthen the electron capture from CO2 to CO2^·-,thereby promoting the photocatalytic CO2 reduction.The existential problems in the process of photocatalytic reduction of CO2 enhanced by oxygen vacancy were explained objectively,and the development prospects were put forward.