The Improvement of Coralline-Like ZnGa2O4 by Cocatalysts for the Photocatalytic Degradation of Rhodamine B

Catalysts

Xiaorui Sun¹  Wanxi Yang¹  Jianwei Shi¹  Meixia Zhu¹  Jia Yang¹ 

[1] Chongqing Key Laboratory of Inorganic Special Functional Materials, College of Chemistry and Chemical Engineering, Yangtze Normal University, Fuling, Chongqing 408100, China;

关键词: photocatalysis;    cocatalyst;    zinc gallate;    rhodamine b;   

DOI  :  10.3390/catal10020221

来源: DOAJ

【 摘 要 】

To date, various methods have been used to synthesize ZnGa₂O₄ material to promote photodegradation performance. However, cocatalysts, which usually play a crucial role in the photocatalyst system, have not been studied extensively in photocatalytic degradation reactions. In this paper, ZnGa₂O₄ semiconducting material was synthesized by a traditional high-temperature solid-state reaction. The as-prepared powder was characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), and ultraviolet−visible diffused reflectance spectroscopy. The results indicate that the as-prepared sample is a highly crystallized granular sample with a bandgap of 4.44 eV and a uniform particle size distribution. Density functional theory (DFT) was utilized to calculate the electronic structure of ZnGa₂O₄. The valence bands and conduction bands were chiefly composed of O 2p atomic orbitals and the hybridization orbitals of Ga 4s4p and Zn4s4p, respectively. The photocatalytic performance was tested via the decomposition of rhodamine B (RhB) under the irradiation of ultraviolet light. Cu, Ag, Au, Ni, Pt, and Pd cocatalysts were loaded on the ZnGa₂O₄ photocatalyst by a photodeposition method. The relatively optimal cocatalyst of ZnGa₂O₄ in the photocatalytic degradation reaction is Au. Thereafter, the effect of loading different usage amounts of the Au cocatalyst for the photodegradation of the ZnGa₂O₄ photocatalyst was studied in detail. The experimental results displayed that the optimum photodegradation activity was confirmed with the 3 wt% Au/ZnGa₂O₄ sample, which was 14.1 times more than the unloaded photocatalyst. The maximum photocatalytic degradation ratio of RhB was 96.7%, with 180 min under ultraviolet light.

【 授权许可】

Unknown