Three Dimensional Printing of Bioinspired Composite Aerogels for Solar Steam Generation

Freshwater scarcity is an escalating global challenge, necessitating sustainable and efficient water purification technologies. Solar steam generation (SSG) has emerged as a promising approach, utilizing solar energy to convert seawater or wastewater into potable water. Aerogels incorporating photothermal agents have been extensively explored for SSG due to their porous structures that support capillary‐driven water transport, coupled with the photothermal agents’ ability to convert solar irradiation into thermal energy to drive evaporation. This integrated functionality facilitates both freshwater production and wastewater treatment. However, traditional aerogels are limited by single‐mode water transport mechanisms, capillary flow within internal pores, which constrain water transport efficiency. Inspired by the dual‐mode water transport mechanisms observed in desert grasses, this study develops reduced graphene oxide‐doped polyacrylamide aerogels featuring engineered longitudinal surface grooves. These aerogels are fabricated using microcontinuous liquid interface production, a high‐speed 3D printing technique, followed by freeze‐drying to tune porosity. Characterization reveals that surface‐grooved aerogels achieve a water transport distance of 2.16 ± 0.11 cm within 10 min and an evaporation rate of 2.1 kg·m −2 ·h −1 under standard solar irradiation (100 mW·cm −2 ). This biomimetic design improves both water transport and solar‐powered water evaporation, offering a scalable and effective approach to advance solar‐driven freshwater production.