Phenol degradation behavior via photocatalytic of ZnO/Ag2CO3/Ag2O nanoparticles

Abstract

The present study successfully conducted the synthesis of ZnO/Ag2CO3/Ag2O nanocomposite using co-precipitate technique and phase transformation route. The resulting nanocomposite photocatalyst were characterized by TEM and UV–vis spectra, while their photocatalytic activities were subsequently tested in the mineralization of phenol solution. Meanwhile, the heterojunction of Ag2CO3/Ag2O over ZnO lattice that influenced the surface-phase structure of the nanocomposites managed to generate higher absorption in visible light region in UV NIR spectra. In addition, the surface phase structure was produced via Ag2O crystal growth over Ag2CO3 which was heterojunctioned on ZnO lattice, thus leading to an effective charge carrier transfer that indirectly suppressed the recombination of photogenerated electrons and holes. The results of the current research on the photocatalytic behaviour of the nanocomposites demonstrated that the phenol peak area for ZnO/Ag2CO3/Ag2O under UV light decreased 25.4 % compared to visible light radiation of 14.1 %. The presence of photo-oxidation products was detected in the liquid phase products in phenol-oxidation even though phenol was not completely removed. Overall, it was remarkable to discover that the formation of Ag2CO3/Ag2O mixed phase heterojunction over the surface of ZnO significantly enhanced the photocatalytic activity under visible light irradiation.