Study of CuS@Au nanoparticles on ZnO nanorods and nanowalls for all-day active degradation of organic dyes

Abstract

Metal oxide semiconductor nanomaterials have been extensively studied for photocatalytic water treatment To enhance their photocatalytic performance different synthetic methods of heterogeneous photocatalysts have been developed for improving energy harvesting of solar light and carrier utilization nowadays In this study we used different substrates to synthesize zinc oxide nanorods and nanowalls Then combing zinc oxide gold nanoparticle and copper sulfide nanomaterial by photochemical reduction and simple chemical reduction method After that adjusting two kinds of parameters with sulfidation time and the concentration of precursor solution cupper (Ⅱ) sulfide for modifying copper sulfide nanoparticles and enhancing the reaction rate of photodegradation After increasing the concentration of precursor cupper (Ⅱ) sulfate the copper (Ⅱ) sulfide nanoparticles synthesized on ZnO-Au or ZnO would transform to copper (Ⅰ) sulfide nanoparticles which own suitable band alignment with ZnO-Au and ZnO and lead to decreasing the carrier recombination rate Moreover the dark catalytic experiments were implemented by adding hydrogen peroxide which would induce the formation of photocatalytic active hydroxyl radicals by copper sulfide without light irradiation Pseudo-first-order kinetic model were employed to quantify the photocatalytic activity and the rate constant increased from 0 0027 (min-1) to 0 0081 (min-1) in the photodegradation experiment and 0 0008 (min-1) to 0 006 (min-1) in the dark degradation experiment of zinc oxide nanowalls and ZnO-Au@CuXS The results also proved that the decoration of copper sulfide nanoparticles can modify zinc oxide effectively on both photocatalytic and dark catalytic reactions that could be applied for all-day active catalyst

Date of Award	2020
Original language	English
Supervisor	Chia-Yun Chen (Supervisor)