Application of molybdenum sulfide-graphene aerogel for solar energy-driven interfacial evaporation

Abstract

Water is one of the most essential human rights, and every human being has the right to drink pure water. Approximately 2.1 billion people worldwide do not have access to safe drinking water, and with a growing population, increasing global industrialization has intensified water stress in many parts of the world. Solar-driven interfacial evaporation, as a sustainable and environmentally friendly technology, transforms external solar energy into thermal energy through a photothermal evaporator to produce fresh water. In this paper, we prepared MoS2-rGO aerogels (MGA) from molybdenum sulfide (MoS2) and reduced graphene oxide (rGO) by one-step hydrothermal and vacuum freeze-drying methods. The prepared aerogels have vertical loose water transport channels and good mechanical properties, and the light absorption of MoS2-rGO aerogels in the solar spectrum (280–2500 nm) reached 86.3 %. The water evaporation rate under one solar radiation intensity condition reached 1.72 kg m−2 h−1 with a photothermal conversion efficiency of 86.5 %. What’s more, the MGA has good salt-resistant properties and cycling stability and always maintains a stable evaporation rate and evaporation efficiency in 15 evaporation cycle tests. In addition, the simplicity and low cost of our aerogel preparation process show a potential way to achieve water purification and desalination in daily life.