A Hierarchically Structured Fe ₃ O ₄ @ PDA ‐Modified PLA Textile With Unidirectional Moisture Transport for Enhanced Photothermal Regulation

Personal heat and moisture management textiles are essential for improving wearing comfort and reducing energy use. However, conventional unidirectional moisture‐wicking fabrics depend mainly on passive evaporation, and their moisture removal ability declines after saturation. Here, a green poly(lactic acid) (PLA)‐based composite textile modified with polydopamine‐coated Fe 3 O 4 nanoparticles (Fe 3 O 4 @PDA NPs) was developed by integrating a hydrophobic‐hydrophilic wettability gradient with photothermal‐assisted evaporation. The textile contains an inner electrospun hydrophobic Fe 3 O 4 /PLA nanofibrous layer, which serves as a moisture‐guiding barrier, and an outer Fe 3 O 4 @PDA‐modified PLA fabric, which acts as a hydrophilic photothermal evaporation layer. This structure enables directional sweat transport from the skin side to the outer surface. By adjusting electrospinning duration, the effects of hydrophobic‐layer thickness on wettability gradient, unidirectional moisture transport, and evaporation were investigated. Increasing electrospinning time from 10 to 40 min raised the cumulative one‐way transport index from 256.32% to 732.17%. Fe 3 O 4 /PLA‐FPPLA‐20 exhibited balanced moisture transport and evaporation, achieving an evaporation rate of 1.199 kg m −2 h −1 . Under dry xenon‐lamp irradiation, its surface temperature rise exceeded 60°C, confirming photothermal performance. These results demonstrate a feasible strategy for PLA‐based textiles with moisture management and light‐assisted thermal regulation, supporting comfortable, sustainable, and energy‐saving future advanced wearable applications in personal thermal management.