Honeycomb-like Microthermal\nTraps on a Photothermal\nSurface for Highly Efficient Solar Evaporation

Solar evaporation is an ecofriendly and practical method\nfor seawater\ndesalination. The photothermal layer, which absorbs solar energy and\nconverts it to thermal energy, plays a crucial role in enhancing the\nefficiency of the evaporator. However, structural design methods for\nphotothermal layers are often complex and energy-intensive. This work\nreports a simple and efficient strategy for fabricating a necklace-like\nbeaded nanofiber self-organized honeycomb-structured photothermal\nmaterial. The honeycomb-like cavities form numerous microscale thermal\ntraps, achieving thermal localization while maintaining high energy\nutilization efficiency, which not only increases light absorption\nbut also facilitates the diffusion and escape of steam. Besides, the\nhydrophobic honeycomb layer separates the photothermal layer and the\ninterface water, which reduces considerable heat conduction loss and\nachieves an effective antisalting performance. These functional features\nendow the evaporator with an evaporation efficiency of 92.9%, and\nthe evaporation rate reaches 2.11 kg m<sup>–2</sup> h<sup>–1</sup> at 1 sun irradiance, demonstrating its great potential for practical\nsolar-driven seawater desalination under natural sunlight.