A robust polypyrrole nanofibrous membrane for versatile applications: Oil-water separation and dye removal

Integrated approaches to oil-water separation and water remediation have significant implications for industrial applications and environmental sustainability. In this study, we focused on developing a versatile polypyrrole nanofibrous membrane (PPy NFM) based on electrospun nanofibrous membrane for the simultaneous and efficient separation of oil-in-water emulsions and removal of dyes from wastewater. PPy NFM with hydrophilicity and underwater oleophobicity exhibited good emulsion separation efficiency (96.7 %) after 20 cycles of gravitydriven filtration. It is also highly resistant to harsh environments, including strong acids, bases, and highconcentration salts. Additionally, PPy NFM demonstrates remarkable removal efficiency for anionic dyes (91.9 % - 99.3 % at natural pH) and cationic dyes (41.3 % - 58.0 % at pH =10) with a strong affinity towards anionic dyes, through multiple interactions, including electrostatic forces, pi- pi stacking, and hydrogen bonding, as supported by experimental evidence and computational simulations. These results highlight the tremendous application potential of PPy NFM in simultaneous oil-water separation and dye removal.