金属硫化物/g-C_(3)N_(4)异质结的构建及其光催化性能改善与应用

Construction,Photocatalytic Performance Improvement and Application of Metal Sulfide/g-C_(3)N_(4) Heterojunctions

金属硫化物和石墨相g-C_(3)N_(4)是两类具有可见光活性的典型光催化半导体材料,两者复合形成的异质结因具有高效可见光活性受到了研究者的广泛关注,在环境污染治理与新能源开发方面具有重要意义。然而,金属硫化物与g-C_(3)N_(4)复合后所形成的异质结仍存在电子-空穴复合率高、催化活性差和能量转换效率低等问题。本文从金属硫化物/g-C_(3)N_(4)异质结的构建、光催化剂性能改善及应用三个方面对近年来的研究进行了综述。在金属硫化物/g-C_(3)N_(4)异质结的构建方面,分别从Ⅱ型异质结、Z型异质结(直接Z型和间接Z型)、P-N型异质结和S型异质结进行总结;从异质结形貌调控、表/界面改性等方面对异质结光催化性能改善进行了归纳,同时概述了金属硫化物/g-C_(3)N_(4)异质结在水解产氢、CO_(2)还原、降解有机污染物、光催化固氮以及光催化杀菌等方面的应用,并提出了金属硫化物/g-C_(3)N_(4)异质结在光催化过程中所面临的诸多挑战,指出利用能带匹配来合理构建异质结是提高金属硫化物与g-C_(3)N_(4)光催化剂活性的有效方法,金属硫化物/g-C_(3)N_(4)异质结大规模的廉价制备是实际应用中需要解决的问题。

Metal sulfides and graphite phase g-C_(3)N_(4)are two kinds of typical photocatalytic semiconductor materials with visible light activity.The heterojunctions formed by the combination of metal sulfides and g-C_(3)N_(4)have been widely concerned by researchers due to its excellent photocatalyti c performance,which has important application prospect in environmental pollution control and new energy development.However,the hete-rojunctions still suffer from high electron-hole recombination rate,poor catalytic activity and low energy conversion efficiency.In this paper,the recent research progress in the construction of metal sulfide/g-C_(3)N_(4)heterojunctions,improvement of photocatalytic performance and application are reviewed.In the aspect of metal sulfide/g-C_(3)N_(4)heterojunctions construction,the typeⅡheterojunction,Z-scheme heterojunction(direct Z-shceme and indirect Z-scheme),P-N heterojunction and S-scheme heterojunction are summarized respectively,and the improvement of hete-rojunctions photocatalytic performance is concluded from the aspects of heterojunctions morphology control and surface/interface modification.At the same time,the applications of metal sulfide/g-C_(3)N_(4)heterojunctions in hydrogen production,CO_(2) reduction,organic pollutants degradation,photocatalytic nitrogen fixation and photocatalytic sterilization are also summarized.The challenges faced by metal sulfide/g-C_(3)N_(4)heterojunctions in the process of photocatalysis are put forward.It is pointed out that the reasonable construction of heterojunctions by using energy band matching is the key to improving the photocatalytic activity of metal sulfides and g-C_(3)N_(4).Large-scale and cheap fabrication of metal sulfide/g-C_(3)N_(4)heterojunctions is a problem to be solved in practical application.