Construction of CoS/Bi2O2CO3 micro-flowers: Efficient degradation of tetracycline hydrochloride over a wide concentration range

Abstract

Herein, the CoS/Bi2O2CO3 heterojunction photocatalyst was successfully fabricated using a facile solvothermal method. The as-prepared CoS/Bi2O2CO3 heterostructure showed faster and higher photocatalytic performance in the photocatalytic oxidation of the hazardous antibiotic contaminant tetracycline hydrochloride (TCH) when compared with single Bi2O2CO3. The optimized 0.5 % CoS/Bi2O2CO3 sample had a photodegradation rate of 96.96 % for 40 mg/L of TCH within 60 min, and the photodegradation rate of TCH within 30 min was 83.93 %. Significantly, the composite exhibits efficient degradation rates for TCH solutions even at concentrations up to 100 mg/L. Thus, the main advantages of CoS/Bi2O2CO3 composites are quick removal time and application to a broad range of contaminant concentrations. Additionally, the impact of pH level on the efficiency of the photocatalytic process was investigated. Particularly, photoelectrochemical characterizations and trapping tests revealed in-depth information about the TCH degradation mechanism. The heterojunction structure can effectively enhance the separation, transfer and synergistic effect of the support to further strengthen the photocatalytic performance. This work demonstrates a new way to prepare green and low-cost heterojunction structured photocatalysts, which can be effectively used to degrade high-concentration TCH wastewater.