A Sustainable Solar Evaporation Strategy: Higher Condensate Yields Through Remote Condensing Structure via Polyelectrolyte Solar Evaporator

Abstract Interfacial solar‐driven evaporation systems are eco‐friendly and promising approaches to produce freshwater and energy. However, the salt accumulation, intricate fabrication process, low evaporation rates, and condensate yields due to environmental stress limit its further practical applications. Herein, an ingenious polyelectrolyte strategy is proposed to effectively control salt accumulation and achieve higher condensate yields through remote and lightweight condensing structures. By sequentially adhering LiNi _0.8 Co _0.15 Al _0.05 O _2‐δ (NCAL) and selectively modifying polystyrene sodium sulfonate (PSS) on a black polyvinyl alcohol sponge, a three‐dimensional (3D) porous foam structure is conveniently constructed (NCAL@PBS), which features a Donnan exclusion with efficient photothermal conversion and salt‐resistance with balanced water supply. The efficient evaporation rate of optimized NCAL@PBS exhibits 2.80 kg m ⁻² h ⁻¹ under one solar irradiation due to non‐radiative relaxation behavior achieved via oxygen vacancy defects (13%) in the NCAL structure, and low evaporation enthalpy (1621 J g ⁻¹ ), guaranteeing stable and efficient evaporation in complicated environments. The NCAL demonstrates nearly 100% antibacterial efficiency against S. aureus under one sun solar irradiation, attributed to photothermal‐induced hyperthermia that damages bacterial cell walls. This work introduces a novel strategy for promoting the water production rate, intelligence, and industrial application of solar‐driven interfacial evaporators.