Photothermal conversion-passive cooling interface achieves efficient evaporation and sustainable thermoelectric power generation

Solar-driven freshwater production coupled with low-grade heat recovery for electricity generation offers a potential solution to simultaneous shortages of freshwater and power shortages. However, achieving highly efficient and sustainable solar-powered water-electricity cogeneration in complex offshore environments remains challenging. This study developed a bidirectional interfacial evaporation and passive thermoelectric generation (PIEG) strategy, forming the basis of a sustainable cogeneration system. The system comprises a photothermal conversion evaporation layer (MoS₂/SA) fabricated from high-purity 1T-phase MoS₂, thermoelectric module (TEG) and passive evaporative cooling interface (MF/SA). The passive cooling interface within the system effectively converts and utilizes the waste heat and latent heat generated during the interface evaporation process, thereby expanding the scope of solar thermal energy utilization. Consequently, the PIEG-based water-electricity cogeneration device requires no external cooling energy input. Under one sun irradiance, exhibits an output voltage of 137.2 mV and an exceptional water evaporation rate of 2.82 kg m⁻² h⁻¹, these values represent enhancements of 172.2 % and 29.5 %, respectively, compared to devices lacking passive interfacial cooling (PIC). Experimental demonstrations confirmed the feasibility of the PIEG strategy for seawater desalination, powering electronic devices and irrigation applications. This work presents a highly promising zero-carbon strategy for achieving self-sufficiency in freshwater, energy, and food resources in remote offshore settings.