Fungal Cell Wall-Graphene Oxide Microcomposite Membrane for Organic Solvent Nanofiltration

High permeability and selectivity have long been pursued in membrane separation technology. However, this purpose remains a paramount challenge for molecular separations mainly limited by the trade-off between permeance and -selectivity. Here, a bio-utilization strategy based on deep understanding of bio-features to fabricate a cell wall-graphene oxide microcomposite membrane for organic solvent nanofiltration is rationally designed. The membrane displays a unique configuration with alternating stacking of cell wall layers and ultrathin graphene oxide layers. Moreover, the interactions between the cell wall and graphene oxide as well as between the membrane and solvent are mainly revealed by all atom molecular dynamics to uncover the possible working principle of the membrane. Specifically, the strong graphene oxide-cell wall interaction and anti-swelling behavior of the cell wall together restrict the expansion of the graphene oxide layer to promise high selectivity. Meanwhile, the well-developed porosity of the cell wall allows a high throughput of various solvents through the membrane, showing excellent rejection for small molecules and solvent permeance as high as 56 L m² h¹ bar⁻¹. The proposed cell wall microcomposite 2D structure could encourage the practical applications of GO-based membranes.