Porous composite membranes based on cellulose acetate and cellulose nanocrystals via electrospinning and electrospraying

•Cellulose nanocrystals exploited as active material for adsorption in porous electrospun fibers.•Superior mechanical properties and negative surface zeta potentials for porous membranes.•Porous electrospun-electrosprayed nanocomposites showed optimal adsorption of dyes. Porous and non-porous cellulose acetate (CA) – cellulose nanocrystal (CNC) electrospun nanocomposite fibers and electrosprayed-electrospun composite membranes were fabricated using two different binary solvent systems. To evaluate the expression of CNC as the active entity in the membrane, dye adsorption studies were carried out using Victoria Blue. To overcome the low surface area of thick porous fibers, a porous electrosprayed-electrospun composite has developed which exhibited 98% dye removal compared to non-porous counterparts (67.9%). The porous membrane with CNC showed an increase of 38mV in surface zeta potential compared to 9mV increases in the case of the nonporous membrane and after the dye adsorption, it maintained the negative charge, indicating that further adsorption is feasible. Moreover, the mechanical properties of porous fibers were found to be ten-fold better than that of nonporous fibers. Creating porous CA-CNC composites is demonstrated as a tool for ensuring better exposure of active materials during the adsorption reaction.