MoO3/g-C3N4复合材料的制备及光催化性能

Preparation and photocatalytic property of MoO3/g-C3N4 composite

以三聚氰胺和四水合钼酸铵为前驱体,采用水热法制备了MoO3/g-C3N4复合光催化剂。利用X-射线衍射仪(XRD)、红外光谱仪(FT-IR)、扫描电子显微镜(SEM)、X射线光电子能谱仪(XPS)及紫外-可见漫反射仪(DRS)等对制备的样品进行了表征。表征结果显示,棒状的三氧化钼负载在层状C3N4表面,复合材料的光吸收能力有一定的增强。材料可见光催化降解亚甲基蓝(MB)溶液的实验表明,三氧化钼和g-C3N4所复合产生的异质结具有较好的吸收光强度及催化降解性能,尤其是5%(质量分数)MoO3/g-C3N4复合材料光催化降解率最好,达到95.7%,高于纯三氧化钼和g-C3N4。自由基与空穴捕获实验表明,·O2-是光催化反应中的主要活性物种。MoO3/g-C3N4复合材料在4个循环周期内表现出了优异的稳定性。

Using melamine and ammonium molybdate tetrahydrate as precursors,a novel MoO3/g-C3N4 composite photocatalyst was prepared by hydrothermal method.The samples were characterized by X-ray diffraction(XRD),infrared spectroscopy(FT-IR),scanning electron microscopy(SEM),X-ray photoelectron spectroscopy(XPS)and ultraviolet-visible diffuse reflectometer(DRS).Characterization results showed that the optical absorption of the composites was enhanced when the rodlike MoO3 was loaded on the layered g-C3N4 surface.The experiment of photocatalytic degradation of methylene blue(MB)solution by material visible light showed that the heterojunction produced by MoO3 and g-C3N4 had better absorption light intensity and catalytic degradation performance,especially the 5%(mass fraction)MoO3/g-C3N4 composite photocatalytic degradation rate was the best,reaching 95.7%,higher than that of pure MoO3 and g-C3N4.Free radical and hole trapping experiments show that·O2-was the main substance in photocatalytic reaction.The MoO3/g-C3N4 composite exhibited excellent stability in four reaction cycles.