Comparative study of zinc oxide nanocomposites with different noble metals synthesized by biological method for photocatalytic disinfection of Escherichia coli present in hospital wastewater.

Binary zinc oxide (ZnO) nanocomposites with different noble metals, silver (Ag) and ruthenium (Ru), were prepared from an aqueous leaf extract of Callistemon viminalis. The biosynthesized photocatalysts were characterized and examined for their photocatalytic disinfection against Escherichia coli isolated from hospital wastewater. The influence of the different noble metals showed a difference in physicochemical characteristics and photocatalytic efficiency between Ag-ZnO and Ru-ZnO.