High-absorption solar steam device comprising Au@Bi2MoO6-CDs: extraordinary desalination and electricity generation

Abstract Solar steam generation as a sustainable water purification technology offers remarkable potential to address global drinking-water shortage. In this work, inspired by the marine benthos coral with dendritic structure, an innovative 3D nanocomposite Au@Bi2MoO6-carbon dots (CDs) solar steamer has been prepared: it exhibits outstanding light absorption of 70%, a photothermal conversion efficiency of 97.1% and an evaporation rate of 1.69 kg m-2 h-1 under one sun illumination. This solar steam generator can be used for seawater desalination and has shown an ion removal rate of ∼100% in the purification of metal ions, which effectively reduces the ion concentration in seawater. In addition, a solar thermoelectric generator (STEG) has been prepared. Compared with the blank thermoelectric generator, the solar thermoelectric generator coated with Au@Bi2MoO6-CDs shows better performance. The maximum recorded electrical output of the STEG is 97.4 μW cm-2, which is a promising potential solution to the world energy crisis. The unique design of biomimetic nanocomposite materials can help achieve better performance for the solar steamer and electricity generator compared to that of a single-component material. This kind of hybrid material can thus offer pathways to the development of solar thermal technologies applicable in various energy-related applications.