Solar Interfacial Evaporation at the Water-Energy Nexus: Bottlenecks, Approaches, and Opportunities

Solar interfacial evaporation (SIE) technology has become an important research content in the water treatment fields gradually. It is low cost and sustainable, especially when water resources are scarce and energy infrastructure is not perfect and can deliver high-quality freshwater. In recent years, along with the rise of new nanomaterials, water evaporation efficiency improved further; additionally, the efficient evaporation system structure design and thermal managements can improve the absorbance and latent heat recovery efficiently. These advanced researches make SIE efficiency is enhanced markedly, especially in small water evaporation equipment driven by solar energy wholly. It can achieve extremely high steam generation rate and possess an extensive application prospect. In this critical review, the photothermal mechanisms and material types of new photothermal materials, the basic structural design requirements of SIE systems primarily are discussed. On this basis, the applications of SIE techniques in the water-energy relations from the microscopic scale to the molecular level in the past decade are summarized. Finally, bottlenecks of the development of SIE technology, as well as the approaches and opportunities in the future, are discussed critically, new ideas are provided for the long-range objective of utilizing renewable energy to generate clean water for environmentally sustainable development.