Enhanced simulated solar sono-photocatalytic performance and antibacterial activities of ZnO/NiO heterojunction nanofibrous membranes

ZnO/NiO heterojunction nanofibrous membranes with different Zn/Ni molar ratios were successfully prepared via electrospinning. The microstructures of the nanofibers were characterized by using scanning electron microscopy, transmission electron microscopy, and X-ray photoelectron spectroscopy. The ZnO/NiO heterojunction nanofibrous membranes showed superior photocatalytic performance on Congo red, particularly under ultrasonic action and simulated solar irradiation. The degradation of Congo red could reach 100% after 40 min with a high degradation constant of 0.064 min(-1). Additionally, the catalyst maintained high photocatalytic activity over five cycles. Furthermore, the heterojunction nanofibrous membranes had good antibacterial effects on Escherichia coli and Staphylococcus aureus with an inhibition zone width of above 8 mm. The generation of superoxide free radical and hydroxyl free radicals played important roles for the heterojunction nanofibrous membranes. This work is significant for studying the potential applications of nanofibers in waste water remediation.