Breathable cooling solutions strengthened by ionic liquids for passive thermal management toward sustainable intelligentization

The rapid development of electronics calls for sustainable thermal management solutions to tackle the rising energy and water demands for cooling. Passive thermal management technologies have emerged as a promising solution to reduce energy and water consumption. In this work, we introduce a breathable cooling solution that can breathe out moisture for electronics cooling during peak hours (i.e., desorption cooling) and autonomously breathe in moisture from ambient air to recover its cooling capacity during off-peak hours (i.e., absorption regeneration). We utilize crystallization-free ionic liquids to prevent uneven temperature distribution, while their high vapor pressure amplifies the evaporation rates and thus achieves significant temperature reductions. Among the evaluated candidates, [EMIM][EtSO₄] stands out, achieving the highest concentration glide of 50.62% and the longest cooling duration. [EMIM][EtSO₄] also records a remarkable temperature reduction of 29.7°C with a heat flux of 4 kW/m², outperforming common phase-change materials, hygroscopic salts, and hydrogels. Cyclic experiments indicate that the mass variations in the desorption and absorption processes gradually stabilize to equilibrium, ensuring sustainable cooling performance. An analysis of the global cooling potential of the proposed device demonstrates unparalleled effectiveness in reducing energy and water consumption. According to the global analysis, this device can also be applied in buildings for indoor thermal regulation, with the global accumulated cooling effects ranging from 2.24 to 4.25 kWh/m², demonstrating versatility for most areas. This nexus approach encompasses interdisciplinary domains of materials science, energy technology, and engineering design, providing robust support for the advancement of sustainable intelligentization reliant on electronics. © 2025 The Authors