Molecular Origins of Hydrophobic-to-Hydrophilic Transition in Polysulfone Membranes: DFT- Rationalized TiO₂/ZnO and Caesalpinia bonducella Functionalization (ao-2026-07882k)

This study investigates the surface modification of polysulfone (PS) membranes using TiO₂-ZnO nanocomposites and Caesalpinia bonducella bio-extract to enhance hydrophilicity and antifouling performance. Membranes were fabricated via non-solvent induced phase inversion and characterized through water contact angle measurements and surface morphology analysis. Density functional theory (DFT) calculations were employed to elucidate the molecular mechanisms behind the hydrophobic-to-hydrophilic transition, revealing significant changes in frontier orbital energies, Mulliken charge distributions, and interfacial hydrogen bonding networks. The synergistic modification strategy demonstrated a progressive and substantial improvement in surface wettability and fouling resistance compared to the pristine membrane. This integrated computational experimental approach offers a rational design framework for developing high-performance PS membranes for water treatment applications.