▎ 摘　　要

Particulate matter (PM) pollution has become one of the most severe environmental issues because of its hazardous effects on human health. The development of a cost-effective and energy-efficient air filter is highly desirable. Nanofibrous membranes have been extensively studied for PM filtration owing to their high specific surface area and the slip effect of air flow on the surface. In this study, graphene oxide/polyacrylonitrile (GOPAN) composite nanofibrous membranes with an olive-like beads-on-a-string structure and with high porosity were controllably fabricated via an electrospinning method. The prepared GOPAN membranes were demonstrated to serve as air filters. The olive-like structure engendered by the GO expansion of the inter-fiber voids substantially reduced the pressure drop of the air filter. The PM2.5 removal efficiency of GOPAN membrane exhibited the highest efficiency (99.97%) with a low pressure drop (8 Pa). The significant enhancement of the air filter properties is attributed to the GO and the designed olive-like bead macrostructures. The GOPAN composite membranes developed in this work have a promising potential for the development and manufacture of a new generation of filter medium with enhanced filtration capacity and a low pressure drop for air purification and other commercial applications.