Modification of the Surface Properties of Core-Shell Semiconductors and Their Effects on the Photodecolorization Activity and Adsorption

Abstract

Semiconductor-based photocatalysts have been extensively studied for oxidative photodestruction of organic pollutants in wastewaters, releasing non- toxic substances such as Azo dyes. Various synthesized catalyst specimens were characterized to determine the correlation between preparation conditions (catalyst type, dopant, microstructure, preparation routs, optical and physicochemical properties) on the photocatalytic activity. Some researchers focused on the process parameters to optimize them to reach higher photoactivity. The specific surface areas, crystalline size, charge and pretreatment of the surface have significant effects on the physical and photocatalytic properties of the semiconductors. The surface sites of catalyst (TiO2) were modified by doping ZnS nanoparticles in the form of Core-Shell structure and the photocatalytic activities were determined by using color degradation and hydrogen production tests. The dye adsorption isotherms of photocatalyst were determined using UV-Vis spectroscopy. The specific surface properties were determined from BET, Zeta meter and Particle size analyzer tests. Photocatalytic decolorization of AR and water splitting test were applied to understand the relation between the surface properties and the photocatalytic activity. The result indicated that core-shell prepared samples had different surface suitable sites to cooperate in photocatalytic reaction.