Keywords: Durability; MoO; Nanomaterials; Flexible membrane; Solar steam generation
Solar steam generation is a promising and efficient strategy to address the issues of water shortage. It is still challenging to design a solar evaporator possessing high evaporation efficiency with eminent durability. Herein, a flexible porous film was successfully designed and synthesized by a simple in-situ solvothermal deposition of MoO2 nanospheres on hydrophilic PTFE film. Metallic MoO2 possesses high chemical stability, low cost and tunable localized surface plasmon resonance (LSPR), which is beneficial for light absorption, photothermal conversion, and operational durability of solar-driven interfacial water evaporator. The absorption spectrum of MoO2 nanospheres almost remains stable after acid, alkali and heating treatment. And hydrophilic PTFE membrane with porous and stable properties are crucial for fast water supply, vapor transportation and stable evaporation performance. As a solar steam generator, the hybrid membrane demonstrates high evaporation efficiency of 91% under one illumination and superb stable evaporation performance in harsh environments, such as acid solution, alkali solution and high-concentration seawater. The as-prepared membrane has the ability to decrease salinity of Yellow Sea water below the World Health Organization standard for drinkable water. The rational design provides enlightenment for potential applications of water evaporation in harsh environments.
