Polyzwitterionic Hydrogels with Tunable Interconnected Pore Structures Enabled by Ion‐Induced Phase Separation

Abstract Hydrogels featuring tunable interconnected pore structures have garnered significant attention in applications requiring controlled mass transport, due to their efficient and adjustable transport properties. However, developing robust fabrication strategies to achieve stable and precisely tailored pore structures remains a significant challenge. Here, a salt ion‐induced phase separation method is presented for the fabrication of polyzwitterionic hydrogels with interconnected pore structures. By leveraging salt ions to modulate polymer chain hydration, this method triggers polyzwitterionic chain aggregation, enabling the formation of interconnected pores. Notably, pore structure regulation is facilely achieved by adjusting salt ion concentration during hydrogel polymerization. When applied to solar steam generation, evaporators based on polyzwitterionic hydrogels with optimized interconnected pore structures demonstrate high‐efficiency mass transport capabilities, exhibiting accelerated evaporation rates of ≈1.950 kg m −2 h −1 . Moreover, these hydrogels demonstrate remarkable stability, sustaining a consistent performance for over 12 h in high‐salinity brine (10 wt.% NaCl). This study provides a practical and scalable method for engineering hydrogel pore structures, offering broad applicability in addressing diverse mass transport challenges across energy, environmental, and biomedical domains.