Liquid Metal–Polyphenol Hybrids for Solar Steam Generation

Interfacial solar steam generation has emerged as a promising strategy for sustainable water desalination; however, achieving high efficiency under practical conditions remains a significant challenge. Here, a natural polyphenol-based gel composite incorporating liquid gallium particles and graphene is presented, engineered for high-performance solar-driven desalination. This synergistic combination enables broadband light absorption, heat localization, and rapid water transport. Graphene and the polyphenol gel matrix enhance light absorption and solar-to-heat conversion, while liquid gallium serves to localize heat; the gel structure facilitates water retention and vapor escape. These features are critical for maximizing solar energy utilization and sustaining continuous water evaporation under real-world conditions. Under one sun irradiation, the system achieves an evaporation rate of 4.8 kg m⁻² h⁻¹ for deionized water and 3.4 kg m⁻² h⁻¹ for seawater. These findings highlight the potential of such multifunctional gel composites in addressing global freshwater scarcity through scalable and energy-efficient desalination technologies.