Search

[Display omitted] • A cellulosic cooling metafabric is reported via multiple scattering mechanism. • The metafabric exhibits high solar reflectivity and daytime cooling efficiency. • A superdurable cellulosic radiative cooling – power generation device can be achieved. 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. [ABSTRACT FROM AUTHOR]

[Display omitted] • A novel phase change approach is used to construct cellulose film with dual pores. • Micro/nano dual pores can enhance total internal reflection and Mie scattering. • The CCF has ultrahigh solar reflectance (97.6%) and high thermal emissivity (95%). • Assembled anti-UV network enables CCF exhibit durable longtime cooling performance. • Strong and flexible CCF can cool electronic devices and protect fresh fruit. Passive daytime radiative cooling technology, which reflects sunlight and emits thermal radiation simultaneously, shows great potential in releasing global warming and energy consumption. Particularly, cellulosic cooling materials, with the advantages of high infrared emissivity, eco-friendly, and easy processing, have gained great attention. However, the poor solar reflectance and the poor durability related to UV and mechanical properties still limited its broad applications. In this work, we developed a novel cellulose composite film (CCF) with a well-defined, hierarchical micro/nanostructure via a rational solvent-induced phase separation technology for efficient and longtime daytime radiative cooling. TiO 2 @PT synthesized via facile ball milling process was used to serve as a dual functional modifier, which can improve the optical, mechanical properties, and anti-UV function of the cellulose-based daytime radiative cooler. Benefiting from the hierarchical dual pores, formed tough interface, and assembled anti-UV functional network, the as-prepared CCF displayed ultrahigh solar reflectance of 97.6 % and enhanced Young's modulus and tensile strength increase by 13 and 4.4 times, respectively. Most importantly, the solar reflectance of CCF is maintained constant after continuous UV tests for 720 h. The work provides a general strategy to simultaneously enhance both the mechanical stability and the UV durability of polymer-based PDRC materials toward large-scale applications. [ABSTRACT FROM AUTHOR]