Photocatalytic Degradation of Toxic Phenolic Compound and Bacterial Inactivation by Ternary Li doped Zn0.5Ni0.5Fe2O4

Abstract

Conventional methods are inefficient to treat water contaminated with persistent organic contaminants. To decontaminate bacteria and 2,4,5-trichlorophenol (TCP) contaminated water, a heterogeneous photocatalysis-based advanced oxidation process was applied in this study. A Li-doped ternary Zn0.5Ni0.5Fe2O4 (ZNF) photocatalyst (Li/ZNF) was synthesized via a facile co-precipitation technique and characterized. The Li/ZNF has a sufficient specific surface area (69.8 m(2).g(-1)), and an appropriate bandgap of 2.89 eV. Under optimal conditions, 10 mg of Li/ZNF photocatalyst degraded 80 % of 50 mg L-1 TCP in 6 h at pH 3 in the presence of 4 mM H2O2. After use, the Li/ZNF photocatalyst was magnetically separated and reused numerous times, with an efficiency of 66 % after the fifth reuse cycle. In the antibacterial time-kill assay, 15 and 25 mg of Li/ZNF inhibited 1x10(7) CFU.mL(-1) of S. Aureus and E. coli bacteria after 60 min of UV exposure, respectively.