Photocatalytic degradation of antibiotics by Nitrogen-doped Zinc cadmium sulfide
Nitrogen-doped Zn0.67Cd0.33S materials(denoted as N-Zn0.67Cd0.33S)were successfully prepared using a viable hydrothermal method wherein N,N-Dimethylformamide(DMF)acted as the nitrogen source.The introduction of nitrogen in N-Zn0.67Cd0.33S was confirmed through morphology and phase analysis employing TEM,XRD and XPS techniques.The photocatalytic degradation performances towards tetracycline(TC)and ciprofloxacin(CIP)over N-Zn0.67Cd0.33S synthesized by adding 13mL DMF(NZCS-13)were investigated under simulated visible light.The results indicated excellent degradation rates of 99.9%for TC and 86.9%for CIP,with corresponding degradation rate constants of 0.2397 and 0.0676min 1,respectively,which were 2.33 and 2.57 times higher than those of pure Zn0.67Cd0.33S(ZCS).The superoxide radical(·O2)was indicated as the primary active species by radical trapping experiments and electron spin resonance tests.The enhanced photocatalytic degradation capability was primarily attributed to the effective separation of photogenerated charges,as supported by PL,UV-Vis DRS and electrochemical assessments.In addition,good cyclic stability was certified by 5consecutive degradation experiments.