Dual‐Plasmonic Ti₃C₂T_x/CuSe 2D/2D Solar Absorber and a Hydrophilic Device for Efficient Solar‐Driven Water Collection

Abstract

Solar water evaporation is an emerging technology for drinkable water generation, while it remains a challenge to develop materials and device for efficient water evaporation and collection. Herein, dual‐plasmonic Ti3C2Tx/CuSe two‐dimensional (2D)/2D hybrids are prepared for high‐efficiency solar water evaporation and a hydrophilic device is designed for efficient water collection. The Ti3C2Tx/CuSe hybrids, which monocrystalline CuSe ultrathin nanosheets are chemically bonded with Ti3C2Tx nanosheets, show efficient photothermal conversion owing to the plasmon‐coupling‐induced strong light absorption and fast charge transfer in the 2D/2D interface. By transferring the hybrids on a cotton piece, the Ti3C2Tx/CuSe membrane displays over 95% of solar light absorption, a stable evaporation rate of 1.893 kg m−2 h−1, and solar‐to‐vapor efficiency of 99.13% under one‐sun irradiation. The membrane can also treat water with more than 20 wt% salinity due to the rich microchannel for ion diffusion. Furthermore, a water evaporation device, which the cambered roof is painted with hydrophilic SiO2, is designed for efficient water collection. The treated roof can efficiently reduce the optical loss and transfer the vapor condensation, leading to a high average freshwater generation of 16.4 kg m−2 in a daily (10 h) natural light irradiation, much higher than other reported devices.