Review on the recent development and applications of three dimensional (3D) photothermal materials for solar evaporators

The global demand for the production of clean water through sustainable and green method has instigated research and development in different arenas. One such noteworthy technique for cleaning of saltwater, polluted and wastewater is by solar evaporation. The basis of solar evaporation in a solar evaporator is the presence of photothermal materials (PTM) and the design of the device. The PTM has attracted immense attention for improving the parameters controlling the thermal management in solar evaporators, thus imparting high efficacy to the system. Recent studies are being conducted on the development of three dimensional (3D) PTM which have demonstrated excellent performances as compared to their two dimensional counterparts. This review encompasses the recent trends and progress in 3D PTMs. The thermal, mechanical and optical properties of the 3D PTMs are dictated by their specific structures, which have been elaborately discussed. The structural design and configuration of different evaporators along with the material used for its fabrication imparting stability to the system has been elaborated. The modified designs for thermal management and apposite transfer of water to the evaporating surface has been highlighted. The gaps still present in the use of 3D PTMs in solar evaporators for improving the absorption of light by the materials and conversion efficiency of sunlight to heat have been identified and prospects for development have been suggested for the production of clean water. Advancement of various types of 3D photothermal materials. [Display omitted] •Emphasis on 3D design of solar evaporators.•Synthesis and characteristics of 3D photothermal materials.•Synthesis and efficacy of natural photothermal materials.•Advantages of the 3D photothermal materials.•Future development of 3D solar evaporators.