Strong, Recyclable, and Sustainable Radiative Cooler with Heterogeneous Interlocking Architecture for Agricultural Thermal Management.

Abstract

Agricultural thermal stress and water loss are critical for sustainable food security in increasingly hot and arid climates, exacerbated by global warming. Passive radiative cooling, leveraging sunlight reflection and deep-space infrared emission, offers a promising solution for agricultural thermal management. However, conventional petrochemical-based radiative cooling materials face environmental challenges from persistent waste, while emerging biomass alternatives often suffer from inadequate cooling performance, poor mechanical robustness, and limited durability. Here, we engineered a robust, sustainable, and recyclable radiative cooling film via a vacuum-assisted hierarchical self-assembly process. This biocomposite features a heterogeneous interlocking structure, which synergistically achieves exceptional solar reflectance (98.1%) and infrared emittance (93.2%), enabling subambient cooling. Field tests demonstrate significant average temperature reductions of 4.6 and 2.4 °C relative to bare soil and commercial reflective mulch, concurrently suppressing soil evaporation and enhancing crop yield. Our material exhibits superior tensile strength (38.7 MPa), significantly outperforming standard commercial reflective mulch (14 MPa). Critically, we introduce a mild water-mediated recycling process achieving near-complete material recovery (>90%), eliminating end-of-life waste accumulation and its detrimental impact on agricultural soils. Combined with exceptional UV resistance, flexibility, and sustainability, this high-performance, recyclable radiative cooler presents a transformative approach for sustainable agricultural thermal management.