Ceramic Fiber Aerogels Based Flexible Solar Steam Generators Enabling Efficient Thermal Localization and High Salt Resistance

Abstract

Solar-driven interfacial evaporation offers a promising strategy to purifying saline water by utilizing solar energy. However, achieving a high evaporation rate often leads to the salt accumulation on the surface of solar evaporators, which seriously impairs light absorption and evaporation performance. Constructing a rational designed solar evaporation with both heat localization and salt resistance is still a challenge. In this work, we propose a ceramic fiber aerogels (CFA) based flexible solar evaporator with metal-phenolic coordination complexes (FeⅢ-TA) as the photothermal conversion layer. The arch-shaped structure significantly increases the steam escape area and effectively suppresses heat loss due to conduction with bulk water. The superior hydrophilic properties of CFA and FeⅢ-TA enable rapid water replenishment on the evaporating surface, thereby ensuring robust evaporation performance and high salt resistance. The FeⅢ-TA@CFA evaporator exhibits a high indoor evaporation rate (~3.3 kg m-2 h-1) under 1.0 sun irradiation with long-term durability and stability (over 30 days). Additionally, a daily water output of ~10.81 kg m-2 is achieved in outdoor sunlight, and the ion concentrations in the condensate is reduced by 3 to 4 orders. Our research provides a ceramic fiber aerogel platform that exhibits both heat localization and salt resistance, enabling efficient solar steam generation.

Keywords: ceramic fiber aerogel, metal-phenolic materials, thermal localization, salt resistance, solar steam generator