Magnetic MoS2 nanosheets as recyclable solar-absorbers for high-performance solar steam generation

Abstract

Abstract To deal with water scarcity, solar steam generation has been widely regarded as one of the promising methods for freshwater production. In this work, for the first time, a novel recyclable MoS2-based nanocomposite (magnetic MoS2 nanosheets) was fabricated via the in-situ growth of nano Fe3O4 on the polydopamine (PDA)-functionalized MoS2 nanosheets, and subsequently applied as the solar absorber in the volumetric evaporation systems to generate solar steam. The magnetic MoS2 nanosheets showed a superhigh solar absorption of over 96% within the whole wavelength range of 200–2500\u202fnm. As a result, a high evaporation efficiency of 79.2% under the low illumination of 2.5\u202fkW\u202fm−2 was achieved. In addition, the magnetic MoS2 nanosheets not only showed the long-term well dispersion in aqueous solution due to the introduction of hydrophilic PDA, but also exhibited a fast and effective separation from aqueous solution with the help of the decorating nano Fe3O4, which much benefited to the continuously efficient solar steam generation and its good recyclability, respectively. Therefore, the MoS2-based nanomaterials in this work showed good prospects for solar energy harvesting.