Moisture‐Thermal Stable, Superhydrophilic Alumina‐Based Ceramics Fabricated by a Selective Laser Sintering 3D Printing Strategy for Solar Steam Generation

Abstract The solar‐driven interface evaporation is one of the most promising technologies for desalination and wastewater purification. However, in the ebb and flow of the tide, water absorbed in the hydrophilic evaporator bottom would significantly change, leading to the shape deformation of the system and further failure of solar steam generation. Here it is reported that the moisture‐thermal stable and superhydrophilic alumina‐based ceramics can be fabricated by a selective laser sintering (SLS) 3D printing strategy. The printed alumina‐based ceramics possess superhydrophilicity. Along the side surface of the printed sample, a 5 µL water droplet can be fast absorbed in 14 ms. Most importantly, they can maintain stable and high evaporation efficiency even after being dried out for ten times, demonstrating the excellent physical resistance to continuous moisture‐thermal transition. Finally, the “I‐shaped” evaporators are printed with salt‐resistant ability, which can maintain a steady high evaporation efficiency in seawater and 20 wt% brine for long‐term steam generation process. The moisture‐thermal stable alumina‐based ceramics prepared in this work will provide inspiration for stable solar steam generation materials, and expand the development of 3D printing functional materials.