Preparation of Dual‐Functional Carbon Nanotube Phase Change Textiles

Carbon nanotube fibers (CNTF) offer great properties for smart textiles, including low density, high strength, and electrical conductivity. However, the dense structure of traditional CNTF limits phase change material (PCM) loading, impeding thermal management applications. Here, this study presents a strategy to fabricate highly oriented porous CNTF (PCNTF) as flexible frameworks for dual‐mode thermal regulation. The horizontally aligned carbon nanotube (CNT) architecture provides exceptional axial thermal conductivity (51.52 W m −1 K −1 ), while the hierarchical porous structure enables a high PCM loading capacity of 73.8%. High‐strength PCNTF with a strength of 450.2 MPa and 6.16% strain is integrated into woven textiles, resulting in lightweight, robust composite phase change textiles. These textiles demonstrate bidirectional thermal regulation, rapid electrothermal response (55.9 °C under 0.36 W cm −2 ) and sustained passive thermal buffering, maintaining a 3–7 °C temperature differential relative to polyester in the range of 40 to 80 °C for over 300 s. This work offers a versatile platform for next‐generation smart textiles with integrated active and passive thermal management capabilities.