A highly efficient bio-inspired 3D solar-driven evaporator with advanced heat management and salt fouling resistance design

Solar-driven evaporators offer a promising approach to obtaining fresh water due to their environmental protection and pollution-free operation, and because they require no other energy input. In this work, we prepared a low-cost fabric roll-based bionic evaporator (FRBE) with advanced heat management and salt pollution resistance based on a three-dimensional (3D) spiral groove structure design for the solar evaporation of seawater. The spiral groove structure, inspired by the vertical water supply of natural trees, had a super-strong regional water circulation ability between the yarns and fibers. The heat energy of the photothermal surface was quickly transmitted to the cold evaporation surface to realize rapid water evaporation, and the low evaporation surface temperature effectively reversed the usual heat loss phenomenon. Under 1.0 sun irradiation, the evaporation rate and evaporation efficiency of the prepared FRBE-4–2 reached 2.89 kg·m−2·h−1 and 130.04 %, respectively. In the evaporation tests with 10 wt% and 20 wt% NaCl solutions, the regional water circulation effectively promoted the dissolution and diffusion of salt on the evaporation surface, reflecting excellent salt pollution resistance performance. Therefore, the 3D spiral evaporation surface design developed in this study provided a new idea for efficient and sustainable steam generation.