Simultaneous Solar Steam and Electricity Generation from Synergistic Salinity‐Temperature Gradient

Abstract

AbstractSolar‐driven interfacial evaporation by localization of solar heating at the air–liquid surface has emerged as a cost‐effective desalination technology. The rapid interfacial evaporation induces simultaneous salinity and temperature gradient between evaporation surface and bulk water, which enables electricity generation but is not comprehensively utilized. Herein, the combination of a thermogalvanic cell (TGC) and reverse electrodialysis (RED) in solar‐driven interfacial evaporation is proposed to extract energy from temperature and salinity gradients simultaneously. Because of the synergistic ion transport effect, the coupling of TGC and RED enables mutual power enhancement by orders of magnitude based on the rational spatial layout and the fabrication of composite electrodes. Finally, a steam‐electricity cogeneration system is designed, which achieves the 1.4 kg m−2 h−1 vapor and 1.11 W m−2 electricity simultaneously under one sun illumination. This concept opens a promising avenue towards a solar‐driven water‐energy nexus.