电化学共沉积制备可见光高催化活性Ag_3PO_4/CNTs/Ni复合薄膜

Ag_3PO_4/CNTs/Ni composite thin films with visible-light photocatalytic activities prepared by electrochemical co-deposition method

采用电化学共沉积法制备了Ag_3PO_4/CNTs/Ni复合薄膜,运用扫描电子显微镜(SEM)、X射线衍射(XRD)、拉曼光谱、紫外-可见漫反射光谱(UV-Vis DRS)对其进行了形貌和结构特性的分析,在可见光下分别考察了复合薄膜光催化降解罗丹明B和刚果红的性能。结果表明,最佳工艺制备的Ag_3PO_4/CNTs/Ni复合薄膜最外层为大小均匀的Ag_3PO_4球形颗粒,平均粒径为20～30 nm,而在其内层则为Ag_3PO_4和CNTs交错的网状结构。Ag_3PO_4/CNTs/Ni复合薄膜的光催化活性和稳定性均明显优于纯Ag_3PO_4/Ni薄膜,且光催化降解罗丹明B的速率常数是纯Ag_3PO_4/Ni薄膜的2.14倍。这都归因于CNTs的高导电性及其与Ag_3PO_4良好的协同效应,有效地促进了光生电子与空穴的分离。

Ag3PO4/CNTs/Ni composite thin film electrodes were prepared using electrochemical co-deposition.The surface morphology and structural properties of the electrodes were characterized using SEM,XRD,Raman and UV-Vis DRS.The photocatalytic properties of Ag3PO4/CNTs/Ni composite thin films were investigated by degrading of rhodamine B(RhB) and congo red(CR) under visible light irradiation,respectively.The results show that spherical Ag3PO4 nanoparticles(average diameter of 20-30 nm) are distributed uniformly on the outermost layer of the composite film when the fabrication process is optimized.The inner layer is network structure which is composed of interlaced Ag3PO4 and CNTs.The Ag3PO4/CNTs/Ni composite thin films exhibit excellent photocatalytic activity with enhanced photocatalytic efficiency and good photostability compared with pure Ag3PO4/Ni thin film.The rate constant of RhB degradation over Ag3PO4/CNTs/Ni composite thin films is 2.41 times that of pure Ag3PO4/Ni thin film.The improvement is attributed to the conductive structure supported by CNTs and its good synergistic effect with Ag3PO4,which favors electron-hole separation and the removal of photogenerated electrons from the decorated Ag3PO4.