Hao Chen, Canjie Lin, Zhen Wang, Yang Liu, Zhenle He, Yaser E. Greish, Shadeera Rouf, Sulaiman Al Zuhair, Bei Liu, Jianping Cao, Lingyue Zhang, Wenbin Wang, Peng Wang
ABSTRACT Solar‐driven interfacial evaporation technology represents a promising decentralized freshwater supply solution that can effectively alleviate global freshwater scarcity. However, the evaporation rate of conventional hydrogel evaporators is often limited by poor pore connectivity and salt‐induced structural shrinkage. Inspired by the salting‐out and salting‐in behaviors of polymers, we fabricated a polyampholyte hydrogel through high‐concentration sodium sulfate, which induces a salting‐out effect to form an interconnected porous structure in the hydrogel. This hydrogel not only exhibits efficient transport channels in pure water but also demonstrates salting‐in characteristics in seawater environments, effectively resisting salt‐induced shrinkage. After functionalization with polypyrrole photothermal nanoparticles, the resulting evaporator achieved a high evaporation rate of approximately 2.18 kg·m −2 ·h −1 under 1.0 kW·m −2 irradiation in real seawater and maintained stable performance without decay over seven days of continuous operation. This study provides a scalable and environmentally friendly design strategy for high‐performance hydrogels in sustainable solar desalination.