Boosting surface charge in biomass nanofiltration membranes for precision water purification

Polyamide nanofiltration membranes face a permeability-selectivity trade-off in precision anion separation and micropollutant removal. Reporting in Nature Water, Wang and co-workers use a carboxyl-rich nanofibrillated cellulose interlayer to restrict piperazine diffusion during interfacial polymerization, thereby tuning surface chemistry and morphology to achieve ultra-high negative charge density and exceptional separation performance.