A 3D self-floating solar vapor generator based on a novel self-healing aero-hydrogel containing peach gum polysaccharide with durability and continuous operation

Abstract

Solar energy interfacial evaporation represents a promising and sustainable approach with considerable potential for seawater desalination and wastewater treatment. Nonetheless, creating durable evaporators for continuous operation presents a challenge. Motivated by natural self-healing mechanisms, this study developed a novel 3D hybrid aero-hydrogel, which exhibited a self-healing efficiency of 89.4 % and an elongation at break post-healing of 637.7 %, featuring self-healing capabilities and continuous operation potential. Especially, the incorporation of hyperbranched water-soluble polymers (peach gum polysaccharide) endow the final solar water evaporators with a lower evaporation enthalpy of water, resulting in that the refined SVG3, with a notable water surface architecture and an expanded evaporation area, achieved a steam generation rate of 2.13 kg m−2 h−1 under 1 Sun. Notably, SVG2 achieved a high evaporation rate of 2.43 kg m−2 h−1 with the combined energy input of 1 Sun and 6 V, significantly surpassing the rate of 1.96 kg m−2 h−1 without voltage input. The results indicate that electrical energy significantly enhances and synergizes with SVG, facilitating continuous operation both day and night through the combined use of solar energy and electrical input. This study offers insightful perspectives for the strategic design of multifunctional hydrogels for solar water evaporation.