MXene-Coated Porous\nFilms Prepared by Breathing Figure\nMethod for Efficient Solar Steam Generation

The interfacial solar steam generation for seawater desalination\nhas attracted attention because of its excellent photothermal performance\nand efficiency. However, the process of preparing evaporators is often\ncomplex and costly, which limits their further practicality. Here,\nwe report an integrated solar evaporator that is easy to prepare and\nhas good salt resistance. The porous structure of poly(methyl methacrylate)\nand polycarbonate (PMMA–PC) films prepared by the breathing\nfigure (BF) method was used as the upper layer, while MXene was deposited\non the as-resulted PMMA–PC film and served as a light absorption\nlayer. Meanwhile, the hydrophilicity of the lower layer of expanded\npolyethylene (EPE) foam can promote the upward transfer of water and\ninhibit heat loss. Under one solar irradiation, the water evaporation\nrate of the composite film was found to be 1.79 kg m<sup>–2</sup> h<sup>–1</sup> in distilled water and 1.67 kg m<sup>–2</sup> h<sup>–1</sup> in a 15 wt % NaCl solution, exhibiting excellent\nevaporation performance and salt resistance. In addition, the PMMA–PC/MXene\nfilms exhibit excellent mechanical properties. Based on these merits\nof the PMMA–PC/MXene solar generator, it may find useful applications\nin practical solar interfacial evaporation. Moreover, the findings\nof this investigation may provide a new opportunity for the rational\ndesign of large-aperture photothermal conversion materials via a simple\nbreathing figure method.