Heterostructured ZIF-67@α-MnO2 based nanofibrous membranes for highly effective removal of low-molecular-weight pollutants from wastewater

Abstract

In this work, a thorn ball-like three-dimensional (3D) heterostructured ZIF-67@α-MnO2 catalyst consisting of ZIF-67 nanocages impaled by α-MnO2 nanorods were robustly embedded in polyacrylonitrile nanofibers by electrospinning technique for highly efficient removal of low-molecular-weight pollutants (LMWPs, like dyes and antibiotics) from wastewater. Benefiting from abundant active sites and enhanced charge transfer abilities provided by ZIF-67@α-MnO2 nanoparticles, the optimal ZIF-67@α-MnO2 nanofibrous membranes (NFMs) showed a significant response towards acid fuchsin (AF) in terms of comparable adsorption capacity (2495 mg/g) and impressive catalytic activity (degradation degree of 99 % AF within 20 min). In addition, the resultant membranes possessed satisfactory versatile catalytic activity toward tetracycline (95.3 %), norfloxacin (98.4 %) and doxycycline hyclate (89.2 %). Besides, the resultant membranes had high permeability of 1302 L·m−2·h−1 driven by gravity and could efficiently treat 370.5 L·m−2 AF (20 ppm), which was significantly higher than that of pure ZIF-67 NFMs (141.8 L·m−2). The successful fabricating of such membrane with extraordinary adsorption and catalytic performance provided a promising approach for high-performance catalytic membranes.