A fabric-based multi-functional solar evaporator with all-weather efficient continuous evaporating capability through photothermal and electrothermal effects

Abstract

Solar-driven desalination is a promising strategy to alleviate the water crisis. However, the intermittent nature of solar irradiation presents a significant challenge in achieving continuous steam generation under all conditions. Most existing methods for fabricating solar evaporators lack scalability, flexibility, and convenience. This study presents an all-weather fabric-based solar evaporation system that integrates carbon nanotubes and in situ anchored copper sulfide nanostructures. The system collects solar energy, leveraging the strong light absorption and excellent conductivity of the fabric, and enables continuous steam generation through alternating photothermal and electrothermal conversion both during the day and at night. Thanks to the synergistic effects of photothermal (1 sun) and electrothermal (5 V) methods, the evaporation system achieves an evaporation rate of up to 5.03 kg m⁻² h⁻¹ in 3.5 wt% NaCl solution, while also reaching 1.93 kg m⁻² h⁻¹ at night. Additionally, during a continuous 7 day test, the system demonstrates excellent stability. Importantly, the evaporation system collects 46.36 kg m⁻² of high-flux condensate during a day of real seawater testing under weak outdoor illumination. Furthermore, this evaporator encompasses antibacterial and UV resistance functions. This study provides a promising approach for efficient, all-weather seawater desalination in complex environments.