Dual Convection Driven Humidity Management: A Novel Route to Efficient and Stable Solar Desalination

ABSTRACT Solar‐driven interfacial evaporation has evolved into a sustainable technology with the potential to alleviate the shortage of freshwater resources. Despite remarkable progress in developing photothermal materials, substrates and hybrid configurations, these approaches aimed at improving the evaporation performance appear to have hit a plateau. This limitation can be attributed to the neglect of thermal convection, a critical factor that significantly impacts evaporator performance. Herein, a wood‐based evaporator featuring a dual convection structure was developed by creating a central cavity in a wood block and integrating MXene photothermal materials. It is worth highlighting that the evaporator delivers an exceptional evaporation rate of 2.16 kg/(m 2 ·h) and a photothermal conversion efficiency of 118% without necessitating the use of special materials or intricate architectures. Simulations revealed that the purposely designed dual‐convection structure effectively regulates the heat distribution and reduces the humidity above the evaporation surface, which proved to greatly enhance both the evaporation rate and the overall photothermal conversion efficiency. Furthermore, the device demonstrates good resistance to saline conditions and long‐term operational stability, even under extreme pH conditions. This work provides novel insights into the design of high‐efficiency, structurally simplified solar interfacial evaporators and broadens the potential applications of wood‐based materials in solar‐driven evaporation systems.