以三聚氰胺和氧化石墨烯颗粒为原料,通过研磨负载、氮气气氛下煅烧的方法制备了石墨相氮化碳/石墨烯(g-C3N4/r GO)复合光催化剂.主要采用TEM、XRD、PL等对其进行表征,研究了其在模拟太阳光下对罗丹明B(Rh B)的光催化性能.PL分析结果显示,相比单一的g-C3N4,g-C3N4/r GO的光生电子-空穴对的复合几率大大降低.光催化结果表明,和单一g-C3N4相比,首次使用研磨负载、氮气保护气氛下煅烧制备的g-C3N4/r GO(2%)光催化反应180min后对Rh B的降解率提高了43.2%.这是因为石墨烯为g-C3N4提供了电子转移场所,实现光生电子-空穴的有效分离,从而提高了光催化效率.本文还考察了添加叔丁醇(TBA)和三乙醇胺(TEOA)后对g-C3N4/r GO光催化的影响,实验结果表明:光生空穴是g-C3N4/r GO光催化体系中的主要活性物质之一.
Graphitic carbon nitride/reduced graphene oxide(g-C3N4/r GO) composite was synthesized by grinding and calcination process. Then it was characterized by transmission electron microscope(TEM), X-ray diffraction(XRD), and photoluminescence spectra(PL). The photocatalytic activity of g-C3N4/r GO was evaluated by degrading rhodamine B(Rh B) under simulated solar light irradiation. The results of PL analysis demonstrated that the recombination of photo-generated electrons and holes was inhibited compared with pure g-C3N4. The results of photocatalytic degradation of Rh B showed that the removal efficiency of Rh B with g-C3N4/r GO(2%) composite in 180 min was improved by 43.2% compared with pure g-C3N4, which was attributed to the facilitated electrons transfer in g-C3N4/r GO composite. The main oxidative species was also detected by addition of TBA and TEOA in the photocatalytic process. The result suggested that holes were mainly responsible for the degradation of Rh B in g-C3N4/r GO photocatalytic system.