Bioinspired aerogel for desalination: Integrating balsa wood microstructures with macroscopic mushroom-shaped architectures for enhanced solar-driven interfacial evaporation

In confronting the crucial matter of freshwater scarcity, solar-driven interfacial evaporation technology presents itself as a promising approach. Nevertheless, designing an evaporator that effectively combines high evaporation rate, salt resistance and stability remains a major challenge. Herein, we present an aerogel evaporator inspired by the vertical water transport channels of balsa wood and featuring a mushroom-shaped macroscopic morphology. This aerogel evaporator is constructed with a porous framework of polyvinyl alcohol and sodium alginate, and diatomite is introduced as the filler. Meanwhile, the use of carbonized green bamboo fiber and carbon black that have undergone hydrophilic treatment as photothermal conversion materials significantly enhances the efficiency of solar absorption and photothermal conversion, ensuring the efficient and stable operation of the evaporator during the solar-driven interfacial evaporation. The aerogel evaporator demonstrates an excellent evaporation rate, reaching 2.33 kg m −2 h −1 , and effectively reduces the evaporation enthalpy of pure water from 2430 J g −1 to 1350 J g −1 . Moreover, it maintains commendable stability over 10 consecutive cycle tests. The unique design of the mushroom-shaped top aerogel evaporators presents a viable and sustainable solution for water purification, potentially playing a pivotal role in mitigating the global freshwater crisis.