Preparation of a novel sonocatalyst, Au/NiGa 2 O 4 -Au-Bi 2 O 3 nanocomposite, and application in sonocatalytic degradation of organic pollutants.

A novel nanocomposite, Au/NiGa2 O4 -Au-Bi2 O3 , as an effective sonocatalyst was prepared through hydrothermal process and high-temperature calcination methods, and then characterized by X-ray diffractometer (XRD), scanning electron microscopy (SEM) and energy dispersive X-ray spectroscopy (EDX). The sonocatalytic activity of Au/NiGa2 O4 -Au-Bi2 O3 nanocomposite was detected through the degradation of some organic pollutants under ultrasonic irradiation. Furthermore, the influences of mass ratio of NiGa2 O4 and Bi2 O3 , ultrasonic irradiation time and used times on the sonocatalytic degradation efficiency were investigated by using Total Organic Carbon (TOC) and UV-vis spectroscopy. The experimental results showed that, because of the existence of Au nanoparticles (AuNPs) served as both conductive passageway and co-catalyst, the nanocomposite sonocatalyst (Au/NiGa2 O4 -Au-Bi2 O3 ) displayed an excellent sonocatalytic activity in degradation of some organic pollutants under ultrasonic irradiation.