Micro/Nanoarchitectonics of Ethanol‐Unfolded Keratin for Dual‐Function Biodegradable Nonwovens

Abstract Nonwoven‐based soilless cultivation holds promise for the cleanup of polluted brownfield areas, yet current substrates remain limited by single‐functionality and inefficient pollutant removal. Existing surface‐functionalized methods often require harsh pretreatment, toxic chemicals, or fall short in interfacial stability, thereby compromising material performance and biocompatibility. Here, a biodegradable Feather Keratin (FK)‐functionalized planting geotextile is introduced through a simple and green ethanol‐induced self‐assembly process. Ethanol triggers FK molecular unfolding and promotes strong non‐covalent adhesion onto jute and polylactic acid fibers, forming a uniform and robust coating without altering the underlying nonwoven structure. The resulting FK‐functionalized nonwovens (FKNWs) exhibit a full transition to superhydrophilicity (water contact angle 121° to 0°), a 3.2 fold increase in liquid retention, and significant mechanical reinforcement (1.8 and 2 fold in the machine and cross directions). Furthermore, the FKNW delivers dual functionality by supporting vigorous plant growth and removing organic pollutants (43.5 mg g ⁻¹ ) while retaining over 90% of protein loading and adsorption capacity after 20 flushing cycles. Owing to its straightforward fabrication, low cost, biodegradability, and integrated cultivation–remediation performance, FKNW represents a practical and scalable solution for the sustainable management and ecological restoration of contaminated brownfield sites.