Exploring interface confined water flow and evaporation enables solar-thermal-electro integration towards clean water and electricity harvest via asymmetric functionalization strategy

Water evaporation is a ubiquitous phenomenon in nature. To fully explore the solar-enabled water evaporation can effectively alleviate the growing concern of shortage of water and also energy source. Although significant advances have been achieved for alternative combination of multifunctional applications to explore the unexploited or wasted thermal/solar energy. However, it remains a great challenge for an effective integration of desired functions into one photo-thermal material for extensive harvesting solar energy. Herein, interfacial confined water flow and evaporation are rationally explored to realize an efficient combination of solar-heating enhanced water-flow-induced power generation and interfacial water evaporation. The effective solar-thermal-electro integration is enabled by one multifunctional Janus material via an asymmetric functionalization strategy. As a proof-of-concept, a bilayer carbon nanotubes (CNTs) film/cellulose paper is employed to function as an efficient solar-driven evaporator. Moreover, the as-prepared CNTs-based paper can be further asymmetrically decorated with hydrophobic polydimethylsiloxane (PDMS) and utilized to collect electricity from the directional water flow under dark and light condition. The monolithic design concept is expected to effectively utilize the water evaporation process for integrated electricity and clean water generation.