光催化CO_(2)还原为CH_(4)研究进展

Research progress in photocatalytic reduction of CO_(2)to CH_(4)

太阳能驱动二氧化碳光催化还原为CH_(4)是缓解全球变暖和能源危机的有效策略,然而,光催化效率较低以及产物选择性差,严重阻碍其大规模商业化应用。探究光催化CO_(2)还原反应机理对解决以上问题有重要参考意义,因此本文对光催化CO_(2)还原为C_(1)产物的基本原理及路径进行阐述,主要综述提高CO_(2)光还原效率以及CH_(4)选择性的方法,如构建异质结、设计结构缺陷、引入单原子催化剂以及其他方法,最后指出CO_(2)光还原CH4面临的挑战和发展前景。

Exploring the mechanism of photocatalytic CO_(2)reduction reaction is of great significance for improving photocatalytic reduction efficiency and product selectivity.In this review,the basic principles and widely accepted pathways of photocatalytic CO_(2)reduction to C_(1)products(formaldehyde pathway and carbene pathway)were first summarized.Secondly,methods to improve CO_(2)photoreduction efficiency and CH_(4)selectivity were summarized,as well as semiconductor modification methods such as constructing heterojunctions,designing structural defects,introducing single atom catalysts,and other methods.The spe-cific analysis is as follows:(1)combining two suitable electronic band structure semiconductors to form a heterojunction can improve the separation efficiency of photogenerated carriers,thus increasing the number of photogenerated charges to promote the multi proton multi electron coupling reaction,and improve the probability of photocatalytic CO_(2)to generate CH_(4)(2)design structural defects can expand the spectral absorption range,adjust the bandgap position,and promote the excitation and separation of photogenerated charges,while the density and properties of vacancies can be adjusted by changing the synthesis conditions;(3)the introduction of single atom catalysts can improve the active site of the catalyst,and adjust the adsorption/desorption strength of reactants,intermediates,and products;(4)other methods:surface regulation and doping.By modifying semiconductors,the photocatalytic efficiency and selectivity for CO_(2)reduction of CH_(4)are greatly improved,providing effective means for the rational utilization of CO_(2).The article concludes by pointing out the challenges and development prospects faced by CO_(2)photoreduction of CH_(4).