Synergistic Dual-Mechanism Localized Heat Channeling and Spectrum-Tailored Liquid Metal Hydrogels for Efficient Solar Water Evaporation and Desalination.

Photothermal hydrogels featuring broadband light absorption abilities and highly hydrated networks provide an appealing mass-energy transfer platform for water evaporation by using solar energy. However, the targeted delivery of solar heat energy to power the water evaporation process remains challenging. Herein, enlightened by metal-phenolic coordination chemistry and camouflaged architecture, photothermal hydrogels with dual-mechanism vaporization structure are tactfully designed via a rational interfacial engineering and integration strategy to enable near-& mu;m heat confinement and highly efficient light-to-heat conversion ability. The spectrum-tailored liquid metal droplet (LMGAs-Fe-III) and optimized carbon-wrapped silver nanowire sponge (Ag@C-750) are integrally built as photothermal promotors/channels and jointly embedded into a highly hydratable poly(vinyl alcohol) hydrogel, denoted as PALGH, to synergistically boost water molecule activation and interfacial vaporization behavior by triggering robust photothermal performance. As a result, under one sun irradiation, the all-embracing PALGH hydrogel evaporation system achieves a brine evaporation rate to a high level of 3.47 kg m(-2) h(-1), and >19 L m(-2) clean water of PALGH is ideally delivered daily when purifying natural seawater. This work offers not only a rational design principle to create sophisticated photothermal materials but also replenishes insight into solar heat generation and water transportation in a cross-media system.