Hollow RuSe ₂ ‐MoSe ₂ @NC Microsphere/Chitosan Aerogel Janus Electrode for Solar‐Driven Photothermal‐Promoted Synchronous Seawater Splitting and Evaporation

Driving seawater electrolysis for hydrogen production and solar-driven seawater evaporation using appropriate materials are important approaches to address energy and freshwater shortages, respectively. Although high-efficiency seawater electrolysis catalysts and solar evaporators have attracted extensive attention, no effective strategy has been developed to combine these two components. The prepared hollow flower-like NC-encapsulated RuSe₂-MoSe₂ and carbon black (CB) are embedded into porous chitosan (CS) aerogel through a catalyst-gel composite integration strategy. The synthesized RuSe₂-MoSe₂@NC/CB/CS exhibits superior catalytic performance, efficient photothermal conversion, and strong water absorption capacity. Moreover, the elaborately constructed asymmetric Janus structure is endowed with effective salt resistance. In alkaline seawater, RuSe₂-MoSe₂@NC/CB/CS exhibits outstanding hydrogen and oxygen evolution reaction performance, requiring only 1.81 V to drive overall water splitting (OWS) at 100 mA cm^-2, which further decreases to 1.77 V under 1 kW m^-2 illumination. As a solar evaporator, it attains an evaporation rate of 2.80 kg m^-2 h^-1 with 92% photothermal efficiency. In this work, the solar-driven photothermal effect is utilized to innovatively achieve synchronous seawater splitting and evaporation on a single electrode. Additionally, a coupled photothermal device designed for synergistic seawater electrolysis and evaporation is successfully operated under natural sunlight.