CdS/RGO/MoS_(2)复合材料的制备及光催化性能

Preparation of CdS/RGO/MoS_(2) composite and its photocatalytic performance

采用简单的水热法制备出CdS/RGO/MoS_(2)复合材料,通过XRD、TEM、UV-Vis DRS、电化学阻抗(EIS)和瞬态光电流响应测试对其进行了表征。结果表明,在可见光照射下,CdS/0.75%RGO/1.0%MoS_(2)复合材料(百分数均为质量分数,以复合材料质量为基准)对甲基橙(MO)具有显著的光催化降解活性和稳定性,其光降解速率(0.05777 min^(-1))分别是CdS(0.0051 min^(-1))、Mo S_(2)(0.0031 min^(-1))、CdS/0.75%RGO(0.0312 min^(-1))、CdS/1.0%Mo S_(2)(0.0258 min^(-1))的11.3倍、18.6倍、1.9倍和2.2倍。使用5次后,降解效果未见明显变化,证明催化体系的稳定性良好。光催化剂活性的提高主要归功于复合材料形成时的费米能级拉平效应能够促进不同半导体之间载流子电子的扩散和转移。

CdS/RGO/MoS_(2)composite was prepared by simple hydrothermal method and characterized by XRD,TEM,UV-Vis DRS,electrochemical impedance(EIS)and transient photocurrent response.The results showed that CdS/0.75%RGO/1.0%Mo S_(2)(mass fraction,based on the mass of composite)composite had significant photocatalytic degradation activity and stability for methyl orange(MO)under visible light irradiation.The photodegradation rate of CdS/0.75%RGO/1.0%MoS_(2)composite(0.05777min^(–1))was those of CdS(0.0051 min^(–1)),MoS_(2)(0.0031 min^(–1)),CdS/0.75%RGO(0.0312 min^(–1))and CdS/1.0%Mo S_(2)(0.0258 min^(–1))11.3-fold,18.6-fold,1.9-fold and 2.2-fold,respectively.After being used for 5 times,the degradation effect had no change significantly,indicating that the catalytic system had good stability.The improvement of activity was mainly due to the flattening effect of Fermi level during the formation of composites,which could promote the diffusion and transfer of carrier electrons between different semiconductors.