Photothermal materials: A key platform enabling highly efficient water evaporation driven by solar energy

Conversion and utilization of solar energy is one of the most important strategies being proposed to mitigate the foreshadowed global energy crisis and environmental issues. Amongst the various solar energy conversion pathways, solar-thermal energy conversion is the most straightforward and efficient. Photothermal materials form the key platform for efficient light-to-heat conversion. The generated heat can be utilized to drive steam generation, which has recently attracted widespread and intense research interests due to its great potential to be a cost-effective and environmentally friendly technique for cleanwater production. In recent years, extensive efforts have been devoted to improving the efficiency of solar steam generation. The exploration of photothermal materials with extremely high light-to-heat conversion efficiency as well as innovative evaporation configurations paved the way for eminent practical applications. In this article, the photothermal effect of different categories of light absorbing materials is reviewed and discussed. The applications of a series of representative photothermal materials for solarsteam generation are introduced and summarized in detail to reflect the state-of-the-art for solar evaporation. Finally, a brief discussion of the future research perspectives in this field are proposed. (C) 2019 Elsevier Ltd. All rights reserved.