Phase change materials as a potential passive cooling solution is widely used to cool electronic devices, since the high temperature accompanied by the continuous operation of these electronic devices significantly affects their efficiencies and causes irreversible damage. However, there is a lack of the feedback on cooling potential and recessive failures such as ineffective cooling due to overuse. Here, we report a self-hygroscopic and smart color-changing Co@Li-PAM hydrogel, composed of polyacrylamide (PAM)-based polymer chains, H₂O molecules, and functional ions including Li⁺, Co²⁺, [Co(H₂O)]²⁺, Cl^-, and Br^-. It has been found that the hydrophilic porous PAM network acts as the main framework with excellent biocompatibility and reliable chemical stability, LiBr acts as the adsorbent in the PAM network to absorb water molecules in the air during electronic device downtime, and Co ions are introduced into hydrogels through coordination bonds formed with amide groups of polymer chains. The reversible transformation between [Co(H₂O)₆]²⁺ and Co²⁺ driven by the water content in Co@Li-PAM triggers color changes, which indicates the current heat dissipation potential of hydrogels. Applying the as-designed Co@Li-PAM hydrogel to cooling commercial polycrystalline silicon solar cells can increase its energy conversion efficiency by 1.26 % under the illumination of 1 kW m^-2. This strategy is expected to provide exotic solutions for the development of electronic devices, carbon neutrality, and global sustainable development goals.

相变材料作为一种潜在的被动冷却解决方案被广泛用于冷却电子设备，因为伴随这些电子设备连续运行的高温会显着影响它们的效率并造成不可逆转的损坏。然而，缺乏对冷却潜力和隐性故障的反馈，例如由于过度使用导致冷却无效。在这里，我们报道了一种自吸湿且智能变色的 Co@Li-PAM 水凝胶，它由基于聚丙烯酰胺 (PAM) 的聚合物链、H ₂ O 分子和包括 Li ⁺、Co ²⁺、[Co( H ₂ O)] ²⁺ , Cl ^- , Br ^-. 研究发现，亲水性多孔 PAM 网络作为主要框架具有优异的生物相容性和可靠的化学稳定性，LiBr 作为 PAM 网络中的吸附剂在电子设备停机期间吸收空气中的水分子，Co 离子被引入到通过与聚合物链的酰胺基团形成的配位键形成水凝胶。[Co(H ₂ O) ₆ ] ²⁺与Co ^{2+的可逆转化}由 Co@Li-PAM 中的水含量驱动引发颜色变化，这表明水凝胶当前的散热潜力。将设计的Co@Li-PAM水凝胶应用于冷却商用多晶硅太阳能电池，在1 kW m ^-2的光照下，其能量转换效率可提高1.26% 。该战略有望为电子设备的发展、碳中和和全球可持续发展目标提供奇特的解决方案。