Facile electrodeposition of ZnO on graphitic substrate for photocatalytic application: degradation of antibiotics in a continuous stirred-tank reactor

This work discusses the possibility of obtaining ZnO film on graphite, which can be widely used for photocatalysis, photocells, photodetectors, etc. The electrodeposition method that was used in this work is simple and manageable, which indicates its promise. Before starting the electrodeposition, the GO plate has been chemically reduced. Then, with a PZC 301 potentiostat, the electrodeposition of ZnO on the GO plate was performed from zinc nitrate solution using 10 consecutive cyclic voltammograms. Three steps were found for the electrodeposition process: nitrate reduction, hydrogen gas formation, and ZnO deposition. The electrochemical properties of the resulting ZnO/GO plate were studied using various measurements such as cyclic voltammetry (CV), chronoamperometry, Mott-Schottky, and electrochemical impedance spectroscopy (EIS). The ZnO/GO plate was found to be an n-type semiconductor with a flat band of E-fb = 0.37 V. To investigate the photocatalytic proprieties of the obtained ZnO/GO plate, we performed a test for cefixime degradation in a continuous stirred-tank reactor. An efficient degradation rate of around 91% was achieved within 6 h. The results showed that this composite could be a promising material for various applications such as degradation of hazardous pollutants, H-2 production, and CO2 reduction.

Automated summary

This study discusses the possibility of obtaining ZnO film on graphite through electrodeposition, which shows great potential for applications such as photocatalysis and photodetectors. The electrodeposition process involves three steps: nitrate reduction, hydrogen gas formation, and ZnO deposition. The resulting ZnO/GO plate was found to be an n-type semiconductor with promising electrochemical properties.