Plasma-assisted green assembly of polydopamine and graphene oxide on wool: Toward bioinspired, multifunctional nonwoven

Multifunctional, environmentally benign surface modification strategies for proteinaceous fibres like wool remain underexplored. This study addresses this gap by integrating a bio-inspired strategy to fabricate multifunctional nonwoven wool fabrics with enhanced UV protection, flame retardancy, and electrical conductivity. Plasma-treated wool was coated with polydopamine and graphene oxide via layer-by-layer assembly, followed by green reduction using ascorbic acid. The modified fabrics exhibited a substantial increase in UV protection, with the ultraviolet protection factor rising from ∼50 (untreated wool) to over 250 after coating with dopamine and graphene oxide, attributed to the strong UV absorption and light scattering of the hybrid coating. Thermal stability and flame retardancy were significantly improved, as evidenced by increased char yield (from 14.2 % to 30.3 %) and decreased peak heat release rate (from 135.5 to 66.1 W/g) in Pyrolysis Combustion Flow Calorimetry tests. Furthermore, conductivity measurements confirmed the successful transformation of wool into a conductive textile, with reduced graphene oxide coated samples enabling the illumination of an LED circuit, while untreated wool remained insulating. This study presents a facile and bio-inspired approach to engineering multifunctional wool textiles through environmentally friendly processes. The improved thermal stability, UV protection, and conductivity make natural wool materials promising for protective and wearable electronics applications.