Photoelectrocatalytic degradation of amoxicillin over quaternary ZnO/ZnSe/CdSe/MoS2 hierarchical nanorods

Quaternary semiconductor film consists of ZnO, ZnSe, CdSe and MoS2 was designed to establish a core-shell structure to achieve the photoelectrochemical oxidation of amoxicillin. The hybrid photoelectrode was fabricated on a FTO substrate from bath deposition methods. The hierarchical ZnSe/CdSe/MoS2 shell was covered uniformly on ZnO nanorod core which provided a direct pathway for electron transfer, large surface area to enhance light absorption and increase active sites. The quaternary photoelectrode exhibited a photocurrent density of 26.86 mA/cm(2) at 0 V us. Ag/AgCl under UV-visible light illumination, which was 31.9 times, 16.7 times and 1.6 times of that of the bare ZnO nanorods, binary ZnO/ZnSe and ternary ZnO/ZnSe/CdSe photoelectrodes, respectively. 10 ppm of amoxicillin was completely degraded in 30 min by the quaternary working electrode with an applied bias of 0.5 V vs. Ag/AgCl. The reusability and stability of quaternary electrode was demonstrated by 3-run recycling experiments. The enhanced photoelectrochemical performance of quaternary photoelectrode can be attributed to the enhancement of light absorption and increased active sites from the coverage of visible-active layers, the accelerated charge separation from the formation of p-n junction and reduced photo-corrosion of CdSe from the protection of MoS2 on the surface. (C) 2018 Hydrogen Energy Publications LLC. Published by Elsevier Ltd. All rights reserved.