A scalable skin-friendly antibacterial radiative cooling textile against extreme heatwaves.

Radiative cooling is an emerging zero-energy personal thermal management technology for mitigating extreme outdoor heatwaves. However, inevitable sweating under such conditions accelerates bacterial growth and degrades cooling performance, causing discomfort and health risks. The absence of reliable textiles to address these challenges limits their practicality. Here, we design a scalable, skin-friendly antibacterial RC textile (Anti-B) for such scenarios, based on hierarchically structured micro-nanofibers formed through hydrogen bonding between chitosan and polyoxymethylene. The amine groups in biologically-derived chitosan impart skin-friendly antibacterial properties without health risks, while the carbon-oxygen bonds in both polymers, combined with micro-nanostructure engineering, ensure sweat resistance, high selective emissivity (80.4%) within the atmospheric window (8-13 μm), and strong solar reflectance (95.6%). As a result, Anti-B exhibits strong antibacterial performance against Escherichia coli, Staphylococcus aureus, Bacillus subtilis, and Pseudomonas aeruginosa, while providing superior cooling compared to commercial cotton and protective clothing (2.0-12.3 °C cooler) under both sunny and cloudy hot scenarios. Moreover, when tailored into a T-shirt, Anti-B demonstrates excellent wearability, including breathability, sweat evaporation rate, and durability, while providing ~5 °C better cooling than commercial cooling counterparts. This work offers a promising pathway for sustainable personal thermal and health management.