聚合氮化碳的制备、改性及光催化还原二氧化碳性能研究

Study on preparation,modification and carbon dioxide photocatalytic reduction performance of polymeric carbon nitride

由过量二氧化碳(CO_(2))排放导致的温室效应使得全球气候变暖问题日益紧迫,在“双碳”背景下,如何资源化利用CO_(2)尤为重要。光催化还原CO_(2)生成化学品和燃料是有望同时解决能源危机和环境问题的途径。非金属半导体聚合氮化碳(PCN)具有可见光响应、化学稳定性高、易于制备等优点,在光催化领域备受关注,但由传统热聚合方法得到的PCN存在比表面积小、电子-空穴对复合严重、对可见光吸收范围窄等不足之处。介绍了光还原CO_(2)的反应机理和PCN的结构,总结了PCN的制备方法以及提升其光还原CO_(2)性能的手段,包括形貌调控、异原子掺杂、缺陷工程和构建异质结等。最后,对目前PCN材料在CO_(2)光还原反应研究中存在的问题进行了分析,并对未来发展方向进行了展望。

The greenhouse effect caused by excessive carbon dioxide(CO_(2))emissions makes global warming increasingly urgent,under the background of“double carbon”,how to utilize CO_(2) is of particular importance.The photocatalytic reduction of CO_(2) to produce chemicals and fuels is a promising way to solve both energy crisis and environmental problems.Non-metal semiconductor,polymeric carbon nitride(PCN)has attracted much attention in the field of photocatalysis due to its visible light response,high chemical stability,easy preparation and low cost.However,PCN prepared by the traditional thermal polymerization method suffers from small specific surface area,serious electron-hole recombination as well as limited visible light response range.The reaction mechanism of CO_(2) photoreduction and the structure of PCN were introduced.The preparation methods of PCN and the modification methods for improved photocatalytic performance were summarized,including morphology control,heteroatom doping,defect engineering and heterojunction construction.Finally,the problems existing in the research of PCN materials in CO_(2) photoreduction were analyzed,and the future development direction was prospected.