g-C_(3)N_(4)/Bi_(2)MoO_(6)复合光催化剂的制备及性能研究

Study on preparation and properties of g-C_(3)N_(4)/Bi_(2)MoO_(6) composite photocatalysts

结合热缩聚法和水热法制备了g-C_(3)N_(4)/Bi_(2)MoO_(6)复合光催化剂,利用X射线衍射(XRD)、傅里叶红外光谱(FT-IR)、扫描电子显微镜(SEM)、透射电子显微镜(TEM)、氮气吸附-脱附曲线、紫外-可见漫反射光谱(UV-Vis DRS)、光致发光光谱(PL)等分析测试技术对材料的结构和性能进行了表征,研究了材料光催化降解罗丹明B(RhB)的效果。结果表明,与纯Bi_(2)MoO_(6)相比,g-C_(3)N_(4)/Bi_(2)MoO_(6)复合材料提高了对可见光的吸收能力,减小了带隙宽度,在可见光激发下提高了降解RhB的光催化活性。其中,5%g-C_(3)N_(4)/Bi_(2)MoO_(6)复合材料对RhB的降解率最高,在可见光照射180 min对RhB的降解率为93%;而同样条件下Bi_(2)MoO_(6)对RhB的降解率为58%。重复性实验表明,复合材料在RhB光降解过程中是稳定的,具有较好的应用潜力。

A series of g-C_(3)N_(4)/Bi_(2)MoO_(6)composite photocatalysts were synthesized by thermal condensation polymerization and hydrothermal method.The structure and performance of the materials were characterized by using X-ray diffraction(XRD),infrared spectrometer(FT-IR),scanning electron microscopy(SEM),transmission electron microscopy(TEM),N_(2)adsorption and desorption process,UV-Vis diffusion reflection spectroscopy(UV-Vis DRS)and photoluminescence spectrum(PL).The photocatalytic degradation of Rhodamine B(RhB)was studied.The results showed that compared with pure Bi_(2)MoO_(6),the g-C_(3)N_(4)/Bi_(2)MoO_(6)composites improved absorbing ability in the visible light region,reduced the band gap width,and exhibited enhanced photocatalytic activity for RhB degradation under visible light irradiation.It was found that the 5%g-C_(3)N_(4)/Bi_(2)MoO_(6)composite showed the highest photocatalytic activity for RhB,and the RhB degradation rate was 93%with visible light irradiation of 180 minutes.Under the same circumstances,the Bi_(2)MoO_(6)degradation rate of RhB was 58%.The recovery test showed that the composites were rather stable during the RhB photodegradation,which had better application potential.