Hierarchical structure regulation for sequential steps in solar vapor generation

Including the transpiration of leaves, water evaporation from solar irradiation is a universal phenomenon in nature. Currently, solar vapor generation allows clean water to be obtained from various waterbodies. Since water is transported through porous structures and evaporates on their surfaces, the properties of the nano-micro structure, especially the surfaces are significantly important. For instance, the surface energy, determined by the localized atomic arrangement, can modify the interactions between water and the substrate. Moreover, the construction of a three-dimensional hierarchical structure can efficiently enlarge the surface area, and the provided channels play a vital role in mass transfer. In this review, we summarize recent research on the structural regulation in tuning the sequential steps in photo-vapor generation. We hope this review can provide a rational and systemic basis for the development of advanced solar vapor generating materials, especially from the view of surface engineering.