Thermal oxygen sensitization modification and its visible light catalytic antibacterial performance for ZIF-8

Abstract

ZIF-8 has excellent antibacterial potential as an important metal organic framework (MOFs) photocatalytic material. However, ZIF-8 is greatly restricted in photocatalytic antibacterial applications due to the wide band gap and only response to ultraviolet light. In this work, the spectral response of ZIF-8 is successfully extended to the visible light region by the thermal gas sensitization treatment technology. Meanwhile, the forbidden band width of the materials is narrowed by about 47%. The results of FTIR, XPS and EDS prove that the elements and functional groups in ZIF-8 have changed, indicating the completion of the thermal gas sensitization reaction. The results of XRD and SEM show that the modification process doesn’t change the crystal structure and morphology of ZIF-8; The result of BET demonstrates that the specific surface area of ZIF-8 decreases slightly after sensitization, but it is still as high as about 1500 m²/g. Photocatalysis studies indicate that the photo-generated charge separation and transfer efficiency of ZIF-8 improve significantly and the recombination reduce substantially after thermal oxygen sensitization. Photocatalytic antibacterial performances reveal that ZIF-8 after thermo-oxygen sensitization can rapidly produce active species such as·O2- and h+ under visible light irradiation, and the bactericidal efficiency exceed 99% against Escherichia coli and Staphylococcus aureus within 20 min. This research provides scientific basis and experimental data for the application of ZIF-8 in microbial management and health protection.