Shape-Customizable 3D Corn Husk-Derived Carbon Evaporator for High-Performance Solar Desalination.

Abstract

Currently, 3D interfacial evaporators have attracted significant attention due to their superior evaporation performance. However, the shape of carbon-based 3D evaporators is often constrained by the original form of biomass materials, which limits their practical applications. Herein, we report a novel strategy for fabricating 3D solar-driven interfacial evaporators with arbitrary shapes (hemisphere, cone, flake, and Z-type) by integrating carbon powder derived from corn shuck (CS) with binders. The silver-doped corn-based carbon (Ag-CCS) material exhibits exceptional photothermal conversion efficiency, achieving surface temperatures of 153.3°C (dry) and 95.7°C (wet) under 1 sun illumination. Among the 3D evaporators, the Z-type design demonstrates the highest evaporation rate of 4.42 kg·m^-2 h^-1, attributed to its porous structure, hydrophilicity, low evaporation enthalpy of adsorbed water (1286.13 J g^-1), and efficient ambient energy absorption and thermal management. Outdoor experiments further validate the Z-type evaporator's superior performance, with a maximum daily water production of 25.1 kg m^-2 and automatic salt-cleaning capability over 20 days. This work paves the way for the scalable fabrication of 3D carbon-based evaporators, offering a viable solution for seawater desalination.