Nano-confined energy network for high-efficient solar steam and power generation

Solar-driven water evaporation is a promising, eco-friendly method for generating clean water and electricity from seawater or wastewater. However, achieving high evaporation rates remains a substantial challenge. In this study, we develop a porous borocarbonitride (BCN) absorber with an energy confinement network, using flour as the carbon source. This network enhances water molecule activation and lowers the enthalpy of evaporation. Additionally, polyvinyl alcohol (PVA) is incorporated to improve mechanical stability and further reduce the energy required for evaporation. The resulting BCN@PVA evaporator demonstrates a high evaporation rate of 2.62 kg m⁻² h⁻¹ and an efficiency of ~88.7 %, achieving steam generation up to five times faster than bulk water. Integrated with a thermoelectric module, the hybrid evaporator delivers a power density of 0.67 W m⁻² under one-sun irradiation and can generate electricity across varied temperatures, representing a clear advance over existing systems. In outdoor conditions, 13 devices in series can power a calculator. This study provides an effective strategy for sustainable co-generation of clean water and electricity, offering solutions for diverse environmental conditions.