Plasmonic wooden flower for highly efficient solar vapor generation

Solar vapor generation has become a promising water purification technology owing to its eco-friendly and energy-saving features. However, it remains as a big challenge to further improve the solar-driven evaporation performance, especially to further increase the efficiency of solar energy utilization. Here, a novel plasmonic wooden flower is fabricated, in which Ag-polydopamine (PDA) core-shell structured nanoparticles (Ag@PDA NPs) are loaded on the wooden flower. The superior structural characteristics of the porous wooden flower and the Ag@PDA NPs provide a synergetic effect. Thus, it exhibits a high light-harvesting absorption of 98.65%. Moreover, the hydrophilic Ag@PDA NPs promote the formation of water films on both sides of the flower petal. Meanwhile, the abundant capillary channels and pinholes in the wood further enhance the heat convection and solar-driven evaporation of the water films on both sides of the petal. With the excellent thermal management performance, the plasmonic wooden flower device has a high vapor generation rate of 2.08 kg m(-2) h(-1) and an ultrahigh solar-to-vapor efficiency of 97.0% under 1 sun illumination, among the best values reported in the literature. It is promising for future water treatment applications in large scale including recovery of metal ions, brine desalination and sewage purification.