Fabrication of ZIF-8/TiO2 electrospinning nanofibers for synergistic photodegradation in dyeing wastewater

Abstract

Semiconductor−metal–organic framework (MOF) hybrid photocatalysts become a significant material to treating dyeing wastewater recently. Zinc-based metal–organic framework (ZIF-8) stands out among numerous photocatalysts for its stability and simplicity to prepare. In this work, the gourd-shaped ZIF-8/TiO2 nanocomposites are prepared in situ on anatase TiO2 by precursor method, and then ZIF-8/TiO2 nanocomposites is supported on PVDF electrospinning nanofibers by blending method to form ZIF-8/TiO2 nanofibers (ZIF-8/TiO2 NFs). We compare the degradation ability of Rhodamine B by ZIF-8/TiO2 NFs with different mass ratios and load rates. When the mass ratio of ZIF-8 to TiO2 is 2:1 and the loading rate is 10%, the photocatalytic degradation efficiency of ZIF-8/TiO2 NFs reached 95.4%, and the degradation remained as high as 88.7% after cycling five times. The characterization results showed that ZIF-8 and TiO2 are connected by N − Ti − O chemical bond, which narrows the band gap and rebars the recombination of the electron-hole pairs. The synergistic action of ZIF-8 and TiO2 largely improves the photocatalytic capacity of ZIF-8/TiO2 NFs.