Sustainable development of high-performance separation membranes based on green-solvent-processed 2D nanoarchitectured nanofiber/networks

Two-dimensional (2D) nanoscale building blocks have gained significant interest in fields ranging from energy and environment to healthcare. Nevertheless, designing such large-sized nanoarchitectured materials based on environmentally friendly solvents has been regarded as a long-standing challenge. Here, the green electrospinning/netting technique employing water/ethanol as solvent is reported to assemble nanofibers and nanowires into 2D nanoarchitectured nanofiber/networks. Manipulation of the simultaneous injection and phase separation of jets and droplets from the Taylor cone enables the formation of nanofibers and nanowire (∼30 nm) networks on a large scale. Benefiting from the simplicity and universality, a wide variety of environmentally friendly 2D nanofiber/networks including waterborne polyurethane, ethanol-soluble polyamide, polyvinyl butyral, polyacrylic acid, and polyvinyl pyrrolidone have been fabricated. The developed nanofiber/nets membranes exhibit unique nanostructure, robust mechanical properties, and satisfactory application performances in areas of gas–solid separation (filtration efficiency of 99.9 % and resistance of 103.8 Pa), liquid–solid separation (rejection efficiency of 99.3 % and permeate flux of 3554.1 L m −2 h −1 ), and gas–liquid separation (waterproofness of 105 kPa and breathability of 3858 g m −2  d −1 ). This research could provide insights into the design and development of high-performance 2D nanomaterials for wide separation applications.