Oxygen-defective MnO2/ZIF-8 nanorods with enhanced antibacterial activity under solar light

Abstract Low-cost MnO2 has been vigorously investigated in the field of catalysis. However, high amount of MnO2 usually needs to be used in the disinfection process owing to their low photocatalytic activity. In this work, modification of MnO2 with zeolitic imidazole framework-8 (ZIF-8) for improving the photocatalytic bactericidal performance was explored for the first time. Specifically, MnO2/ZIF-8 exhibited complete inactivation of multi-drug resistant Escherichia coli (E. coli) at a low concentration (3.24 μg/mL) with simulated solar irradiation. The 1O2 rather than O2− or OH was identified as the major reactive species for the bacterial inactivation. Mechanistic studies indicated that the superior bactericidal property of MnO2/ZIF-8 than the pristine material could be ascribed to the increased surface oxygen vacancies (OVs) amount and an inhibited electron and hole recombination. This study provides a novel type of photocatalyst for antibacterial application and may shed light on designing MnO2 based low-cost nanocomposites with photocatalytic bactericidal capability for the practical water disinfection treatment.