Preparation and Photocatalytic Degradation Performance of C@CdxMn1−xS to Tetracycline Hydrochloride

Abstract

CdxMn1−xS solid solutions were synthesized by incorporating Mn2+ into CdS and the optimal ratio of Mn2+ to Cd2+ was explored via photocatalytic degradation performance for tetracycline (TC). Subsequently, the composite catalyst C@CdxMn1−xS was prepared by loading CdxMn1−xS onto the biomass gasification carbon residue (C) by hydrothermal method and characterized by various characterization tests. The optimal TC photodegradation condition and degradation mechanism catalyzed by C@CdxMn1−xS was investigated. The results showed Cd0.6Mn0.4S had the optimal photocatalytic degradation efficiency, which is about 1.3 times that of CdS. The TC photodegradation efficiency by [email protected] prepared at the mass ratio of C to Cd0.6Mn0.4S of 1:2 was the best, which was 1.24 times that of Cd0.6Mn0.4S and 1.61 times that of CdS. Under the optimal conditions (visible light irradiation for 60 min, [email protected] of 20 mg, 40 mL TC solution of 40 mg/L), the TC degradation efficiency was 90.35%. The degradation efficiencies of 20 mg/L levofloxacin, ciprofloxacin, and 40 mg/L oxytetracycline catalyzed by [email protected] range from 89.88% to 98.69%. In the photocatalytic reaction system, •O2− and h+ are the dominant active species, which directly participate in the photocatalytic degradation reaction of TC, and •OH contributes little. The work provides a strategy to improve the photocatalytic performance of CdS for photocatalytic degradation antibiotics, and opens an interesting insight to deal with solid waste from biomass gasification.