碳空位改性g-C_(3)N_(4)的制备及光催化性能

Preparation and photocatalytic performance of modified g-C_(3)N_(4) by carbon vacancy

以三聚氰胺为原料,采用高温二次煅烧法合成了具有{100}和{002}晶面的碳空位g-C_(3)N_(4)材料(V_(C)-C_(3)N_(4)),通过XRD、SEM、EDS、EIS、DRS等对其形貌和晶型结构等特性进行表征。碳空位的引入提高了电子传递能力并缩小了禁带宽度,共同促进了光催化降解活性。以罗丹明B为目标污染物的光催化降解实验表明,V_(C)-C_(3)N_(4)比g-C_(3)N_(4)对罗丹明B的光催化降解能力更强,降解率由53.0%提高至89.2%。自由基捕获实验表明超氧自由基为主要的活性物种,羟基自由基是次要的活性物种。

The carbon vacancy modified g-C_(3)N_(4)(V_(C)-C_(3)N_(4))with{100}and{002}crystal planes was synthesized by the high-temperature calcination method using melamine as the raw material.The morphology and crystal structures of g-C_(3)N_(4) were characterized by XRD,SEM,EDS,EIS and DRS.The results showed that the introduction of carbon vacancies would increase the electron transfer capacity and reduce the bandgap,which simultaneously promoted the photocatalytic degradation activity.Rhodamine B was used as the target pollutant to analysis the photocatalytic degradation performance of V_(C)-C_(3)N_(4).The results showed that V_(C)-C_(3)N_(4) had a stronger photocatalytic degradation ability to rhodamine B than g-C_(3)N_(4).The degradation rate of rhodamine B increased from 53.0%to 89.2%.The results of free radical capture experiments showed that superoxide radical was the main active species and hydroxyl radical was the secondary active species.