Dual functional oyster shell-derived Ag/ZnO/CaCO nanocomposites with enhanced catalytic and antibacterial activities for water purification.

Transforming biological waste into high value-added materials has attracted extensive current research interest in the wastewater treatment field. In this study, oyster shell-derived CaCO was used as a solid support to construct efficient Ag/ZnO/CaCO extract. As compared to binary Ag/CaCO and ZnO/CaCO, the as-obtained Ag/ZnO/CaCO exhibits excellent performance for the reduction of 4-nitrophenol (4-NP) with a reduction rate of 97.6% within 8 minutes. Furthermore, Ag/ZnO/CaCO exhibited superior antibacterial activity in inhibiting the growth of () and () with minimum inhibition concentrations (MICs) of 60 μg mL and 30 μg mL, respectively. The observation of the superior activity for the reduction of 4-NP and antibacterial test of Ag/ZnO/CaCO can be attributed to the synergistic effect of Ag, ZnO and the oyster shell-derived CaCO. This study provides a strategy in developing highly efficient catalysts for the reduction of 4-NP and antibacterial agents based on the oyster shell-derived CaCO.