Multifunctional Hydrogel Sorbents with Hybrid Thermal Strategies for All-Weather Atmospheric Water Harvesting

Sorption-based atmospheric water harvesting (SAWH) represents one of the most promising strategies to mitigate global freshwater scarcity, capturing atmospheric moisture under low humidity without the need for energy-intensive cooling. Yet, widespread deployment remains constrained by slow sorption–desorption kinetics, limited uptake capacity, and the structural fragility of advanced sorbents. Many state- of-the-art sorbents are also nearing their thermodynamic limits, leaving little scope for further performance gains through materials development alone. Despite progress achieved with radiative cooling (RC) and solar heating, current SAWH technologies still cannot deliver reliable, continuous, and scalable water generation across diverse climates. The CoolHeatHarvest project addresses these challenges through integrated materials engineering, adaptive thermal management, and holistic system design. Its novel multi-mode thermal framework combines RC, solar heating, and low-voltage Joule heating to ensure on-demand, round-the-clock water release, including under low-light and nighttime conditions. Customized 3D-printed scaffolds reinforce fragile hydrogel sorbents while acting as embedded Joule-heating elements, accelerating desorption and improving long-term durability. In addition, innovative thermal concentration strategies pioneered by the host institution will amplify radiative and photothermal effects to enhance efficiency and yield. In parallel with these advances, COMSOL Multiphysics modelling will couple microscopic sorbent–thermal interactions with macroscopic system simulations to deliver fundamental mechanistic understanding and guide the development of novel concepts, enabling robust, predictive, and scalable device optimization. By simultaneously overcoming materials-level limitations and system-level inefficiencies, CoolHeatHarvest establishes a pathway to practical, sustainable, and climate-resilient atmospheric water generation.