Bio-inspired Micro-architecturing of 3D Aerogel Evaporator for Highly Efficient Solar Seawater Desalination

Authors：Jianqiushi Ma, Xuhui Sun, Yi Liu, Liwei Wang*, Meng An*, Yusuke Yamauchi* and Zhanhui Yuan*

Abstract：Solar interface evaporators for desalination have gained a growing research interest due to its potential for sustainable water production. However, an efficient balance in performance for heat management, water transport, and salt tolerance and rejection is rather difficult to achieve in actual applications. Inspired by the vascular bundles arranged in order in parenchyma cells of seagrass, this study reports the vertical arrangement of 3D aerogel formed by the hybridization of sodium alginate and reduced graphene oxide (denoted as SrGAE) to demonstrate a highly efficient solar interfacial evaporation for desalination. Due to the biomimetic macro-architecture with vertically arranged channels, SrGAE successfully achieves a shortened distance for water transmission and expanded channel for salt discharge in comparison to a traditional evaporator. Furthermore, SrGAE can absorb external energy through evaporative cooling and reduce the water-evaporation enthalpy, achieving an excellent solar-steam conversion efficiency. Such properties of SrGAE enable a continuous evaporation of 20 wt.% brine for 8 hours under one sun illumination, thus achieving an evaporation rate of 3.7 kg·m-2·h-¹ and an outstanding solar-vapor conversion efficiency of 106 %.

DOI:https://doi.org/10.1016/j.nanoen.2025.110781