Green Fabrication of Synergistic Adsorption-Photocatalysis Nanofiber Composite Membranes for Enhanced Dye Removal

The widespread discharge of dye-laden wastewater poses serious environmental and health threats due to its high toxicity and poor biodegradability. Conventional treatment methods are often energy-intensive and prone to secondary pollution, highlighting the need for efficient and sustainable purification materials. Herein, a green and scalable three-step strategy is developed to fabricate multifunctional ethanol-soluble polyamide/activated carbon/polydopamine/layered double hydroxide (EPA/AC/PDA/LDHs) nanofiber membranes. The process-combining blend electrospinning, biomimetic in situ polymerization, and room-temperature LDH growth-completely avoids toxic solvents and high-temperature calcination. The hierarchical porous structure, formed through the synergistic integration of AC, PDA, and LDHs, provides abundant active sites, strong interfacial adhesion, and enhanced charge transfer capability. The optimized membrane achieves removal efficiencies of 96.3% for methylene blue and 93.2% for Congo red, maintaining over 70% performance after five reuse cycles. Mechanistic studies reveal a synergistic adsorption-photocatalysis mechanism, where pollutants are captured via electrostatic attraction and π-π stacking, then degraded by reactive radicals generated under visible light through PDA-enhanced charge separation. This work offers a solvent-safe, energy-efficient, and recyclable pathway for advanced wastewater treatment and establishes a generalizable paradigm for green fabrication of environmental remediation materials.