Advanced Designs for Solar Vapor Generation

Photothermal-based solar vapor generation, which harvests solar energy and localizes the generated heat by black absorbers for water evaporation, is thought as an advanced clean energy technology for solar energy utilization. So far, solar-driven water evaporation has achieved significant progress, with water evaporation rates breaking the thermodynamic limit of 1.48 kg·m⁻²·h⁻¹. This has also caused extensive attention in various applications, such as desalination and wastewater treatment. However, focusing on the evaporation rate alone cannot make this field great breakthroughs toward practical application. A lot of crucial factors behind the highly efficient solar vapor generation shall be re-considered to accelerate the development of this field. In this Perspective, the promising solar energy conversion technology of solar vapor generation is firstly discussed. Then the fundamental aspects of how to design the high-efficiency solar evaporators are discussed. Finally, the latest viewpoints on breaking the thermodynamic limit of solar vapor generation will be discussed to potentially boost the evaporation performance.