Graphene oxide functionalized polyvinylidene fluoride nanofibrous membranes for efficient particulate matter removal

The functionalization of nanofibrous membranes (NFMs) is a prevailing and promising strategy to prepare highly efficient air filters for high-precision filtration. Graphene oxide (GO), due to its functional chemical groups, high mechanical properties , electrical conductivity , and excellent compatibility, has been widely applied in modification of polymer materials. In this work, two-dimensional graphene oxide (GO) nanosheets are introduced into PVDF NFMs through the use of the GO/PVDF blending-electrospinning and GO@PVDF surface coating methods to prepare a highly efficient air filter, respectively. Different GO loadings lead to NFMs with diverse surface properties, static electricity, nanofiber diameters, and air filtration performances. The basic properties, filtration performance and effects of the GO loading strategies of the optimized GO/PVDF and GO@PVDF NFMs are systematically compared and analyzed. In general, blending GO in a PVDF solution before electrospinning may significantly enhance the spinnability and static electricity. Meanwhile, GO with lamellar structure is of great benefit to provide the nucleation basis for β-PVDF, which can significantly endow the membrane with good particle capture capacity. The obtained GO/PVDF NFMs show a higher PM 2.5 removal efficiency of 99.31% and better reusability than the pristine PVDF NFMs (93.74%) and GO@PVDF NFMs (95.41%). This work reveals that blending GO in an electrospinning solution is a practical modification technique to prepare a high-efficiency air cleaning membrane.