An engineered superdurable cellulosic radiative cooling – Power generation wearable metafabric

Incorporating zero-energy-input cooling-power generation technology into personal thermal management (PTM) systems is a promising solution for thermal energy utilization but remains a huge challenge due to lacking of effective assembly technology. In this work, a sustainable, cost-effective, superdurable, and nanostructured cellulosic metafabric (CWF) is reported that exhibits well radiative cooling function to achieve high-performance power generation. Through tailoring the viscoelasticity and optical performance in the electrospinning process, this metafabric demonstrates a unique micro/nano structure and anchored MOF assembly, 95.7 % solar reflectivity, 0.94 infrared emissivity, high mechanical strength, washability, surface hydrophobicity, and UV resistance can be achieved. This metafabric exhibited high cooling efficiency of 5.7 °C during direct sunlight in summer and anti-washing and UV stability. Furtherly, we coupled the CWF (as the cold sink) with a commercial thermoelectric device to assemble a power generation device. The device can output average voltage of 200 mV with an average temperature gradient of ≈20.1 °C under stimulated sunlight and shows superdurable power generation performance even after washing or folding (7000 cycles) use. An outdoor test demonstrated it can deliver a high output voltage of 519 mV in Nanjing, China. The cooling metafabirc shows great promise for practical applications in wearable power generation devices.