Double-Plasma Ti3C2Tx/Ag@SiO2 Gel Micro-/Nanoporous Structures for Improved Water Transport and Efficient Solar Steam Generation

Abstract

Interfacial solar steam generation is considered the next-generation desalination and sewage treatment technology. However, realizing solar evaporators with broad-spectrum absorption, efficient thermal conversion, and high stability remains a challenge. The high light-trapping surface structure and fast water transport channels of the evaporator improve the evaporation efficiency, and solar evaporators have great potential in the field of solar steam generation. Herein, the mixture of transition-metal carbide (Ti3C2Tx) and core–shell Ag–SiO2 nanoparticles (Ag@SiO2 NPs) is fabricated as a three-dimensional (3D) vertical porous Ti3C2Tx/Ag@SiO2 gel evaporator via ice templating technology. The synergistic interaction between dual Ti3C2Tx–Ag plasma materials confined in a cross-linked microcapillary structure realizes 97.6% wide absorption in the wavelength range of 250–2500 nm. The SiO2 coating on the surface of Ag NPs can inhibit the oxidation of Ag NPs and conduct heat collection management. The 3D vertically cross-linked porous structure promotes efficient water transport and improves the mechanical strength of the evaporator. The Ti3C2Tx/Ag@SiO2 gel evaporator exhibits a high evaporation rate of 1.42 kg m–2 h–1 and a photothermal conversion efficiency of 98% under 1 sun illumination. The Ti3C2Tx/Ag@SiO2 gel evaporator shows great application prospects in seawater desalination and sewage purification.