摘要
以g-C_(3)N_(4)为光催化剂进行分解水制氢和污染物降解的研究受到广泛关注,但如何采用简单易行的方法制备出高效、稳定且具有良好光热稳定性的催化剂是本领域的研究热点和难点。本文采用一种简单的水热法在g-C_(3)N_(4)表面引入更多的氨基,通过SEM、TEM等研究表面氨基化对g-C_(3)N_(4)表面形貌的影响,发现氨基化对其边缘位置的形貌影响较大;XRD、FTIR、UV-vis、XPS等分析表明表面氨基化反应对g-C_(3)N_(4)的主体结构没有破坏;光催化分解水制氢和罗丹明B降解性能表明,当采用浓度为15wt%的氨水处理时,g-C_(3)N_(4)对罗丹明B(RhB)的光催化降解性能也达到最优,90 min的降解率为98.12%,是g-C_(3)N_(4)的1.55倍(63.28%),过高或过低的氨水浓度均不能使光催化性能达到最优;同时其分解水制氢速率性能最优(180.24μmol·g^(-1)·h^(-1)),为g-C_(3)N_(4)的1.46倍(123.04μmol·g^(-1)·h^(-1));光电性能测试结果发现表面氨基化后光催化性能的增强机制可归结为:氨基是供电子基团,氨基含量的增加有利于光催化反应的发生,过度的氨基化导致离域三嗪环结构的破坏,光催化性能大幅降低。
The research of hydrogen production from water decomposition and pollutant degradation using g-C_(3)N_(4) as photocatalyst has been widely concerned,but how to prepare efficient,stable and good photothermal stability catalyst by a simple and easy method is the research hotspot and difficulty.A simple hydrothermal method was used to introduce more amino groups on the surface of g-C_(3)N_(4).The influence of surface amination on the surface morphology of g-C_(3)N_(4) was studied by SEM and TEM,and find that amination has a great influence on the morphology of edge position.XRD,FTIR,UV-vis,XPS analysis show that the surface amination reaction dose not damage the main structure of g-C_(3)N_(4).Studies on photocatalytic water hydrogen production and rhodamine B(RhB)degradation performance show that the highest hydrogen production rate of g-C_(3)N_(4) when treated with 15wt%ammonia(180.24μmol·g^(-1)·h^(-1)),which is 1.46 times higher than that of g-C_(3)N_(4)(123.04μmol·g^(-1)·h^(-1)).At the same time,the photocatalytic degradation performance of RhB also reaches the optimum.The degradation rate of RhB is 98.12%in 90 min duration irradiation,which is 1.55 times higher than that of g-C_(3)N_(4)(63.28%).Neither too high nor too low ammonia concentration can make the photocatalytic performance reach the optimum.The photoelectric performance test results show that the mechanism of the enhancement of photocatalytic performance after surface amination can be attributed to the fact that the amino group is an electron donor group.After excitation,the increase of amino content is conducive to the occurrence of photocatalytic reaction,and excessive amination leads to the destruction of the delocalized triazine ring structure,and the photocatalytic performance is greatly reduced.
作者
李晓莉
LI Xiaoli(College of Science,Xi'an Shiyou University,Xi'an 710065,China)
出处
《复合材料学报》
EI
CAS
CSCD
北大核心
2024年第6期3070-3078,共9页
Acta Materiae Compositae Sinica
基金
陕西省数理基础研究项目(22JSY001)。
