Reduced graphene oxide aerogel with the dual-cross-linked framework for efficient solar steam evaporation

Solar-steam generation is a promising technology to alleviate the water shortage problem by capturing solar energy. Photothermal aerogels, especially graphene-based aerogels, show great promise for solar-driven water evaporation due to the unique properties, such as broadband solar absorption, lightweight, high and evaporation rate. However, how to improve the mechanical properties of aerogels still remains a great challenge that has limited their practical applications so far. Herein, we utilized GO nanosheets and sodium alginate as raw materials, elastic graphene oxide framework (GOF) was formed through covalent cross-linking and hydrogen bonds under mild conditions. After the simple reduction, featured with a three-dimensional (3D) interconnected porous network structure, the novel high flexibility rGO-SA aerogels with good mechanical property were obtained and possess outstanding broadband light absorption (95.87%), low thermal conductivity (0.049 W m −1 K −1 ), high salinity removal rate (99.28%), and high evaporation rate (1.86 kg m −2 h −1 ) under 1 solar radiation. The dedicated designed graphene-based aerogels will be an attractive photothermal material for seawater desalination applications. • A dual-cross-linked framework is proposed to increase mechanical properties. • The rGO-SA aerogel has the properties of flexibility and lightweight. • The aerogel possesses robust photothermal conversion ability.