Setaria-Like ZIF-8@ZnO/PVDF Nanofiber Membranes for Efficient Piezoelectric Photocatalytic Degradation of Tetracycline

The continuous existence of antibiotic pollutants presents a grave threat to the ecological environment. This study aims to develop an efficient and stable hybrid photocatalytic membrane for degrading tetracycline (TC) in aqueous solutions. Inspired by setaria, the novel hybrid ZIF-8@ZnO/polyvinylidene fluoride (PVDF) membranes (PZM) are successfully prepared by in situ growth of ZnO nanowires on PVDF membranes via hydrothermal synthesis, followed by incorporation of the metal–organic framework material ZIF-8. The preparation conditions for ZnO nanowires are systematically optimized. Results indicate that the prepared ZnO/PVDF membranes (PZ) exhibit optimal photocatalytic activity when the ZnO precursor concentration is 0.5 wt% and the hydrothermal growth time is 2 hr. Additionally, with the increased stirring rate of the reaction system, the superior piezoelectric properties of the PVDF nanofiber membranes are applied to accelerate TC degradation. Most importantly, compared to pure PZ membranes, the hybrid PZM membranes significantly enhance the photocatalytic degradation efficiency of TC. Under visible light irradiation, the hybrid PZM nanofiber membranes achieve TC degradation efficiency of 75%, which is increased by 66% compared to that of ZnO powder. This investigation offers a potentially viable approach for the design and construction of hybrid photocatalytic materials for effectively eliminating emerging organic pollutants from water.