Facile and sustainable fabrication of carbon membranes through mechanical rubbing for efficient nanofiltration

Although having shown great promise in gas separation, reverse osmosis , and nanofiltration , preparation of carbon membranes, which commonly involves elaborate high-temperature pyrolysis or exfoliation-reassembly, still suffers from complicated fabrication procedure and/or high production cost. In this study, we pioneered the preparation of continuous asymmetric carbon membrane through facile mechanical rubbing of a pencil graphite. Among them, 2B-type pencil with 64 wt% graphite exhibited superior nanofiltration performance (Congo Red rejection rate of 99.4% and water flux of 21.91 L·m −2 ·h −1 ·bar −1 ). Long-time operation confirmed its excellent stability. Of particular note, the spent membrane could be facilely recovered by erasing, resulting in not only zero pollutant discharge but also full recovery and reutilization of the substrate. The above protocol is anticipated to pave an avenue for facile and sustainable production of versatile carbon membranes with superior separation performances.