Biomass-based high-efficiency solar-driven interface evaporator based on natural pomelo peel with multi-curvature gradient structure

Abstract

Interfacial solar-driven steam generation (ISSG) applied to desalination is considered as a promising technology to solve freshwater crisis. However, challenges remain in the high cost of raw materials, complex manufacturing and the inability to scale. In this paper, a novel interfacial solar-driven evaporator based on ultra-black carbon black-coated pomelo peel (UB-PP) is proposed for high-efficiency desalination, the synergistic effect of natural PP with unique structural properties and the surface high absorption rate photothermal material endows the UB-PP evaporator with high evaporation efficiency, in which the unique multi-curvature gradient and interconnected porous structure is the key to achieving superior solar water evaporation. Under the local high photothermal conversion heat on the surface, the ubiquitous structure provides timely self-water supply, fast water transport, water activation and multi-channel steam release, resulting in the UB-PP evaporator with excellent water evaporation rate of 1.81 kg·m−2·h−1 under 1 sun. Benefiting from the "Turning waste into treasure" strategy and simple preparation method, the overall material cost is as low as $2.7 m−2, enabling the practical large-scale application of UB-PP in desalination and providing a cost-effective management strategy for biowaste.