Recent advances in fiber-based materials for solar-driven interfacial evaporation: A comprehensive review

Solar-driven interfacial evaporation (SDIE) offers an efficient and sustainable alternative to conventional desalination. Fibrous materials have attracted attention as a promising platform for SDIE, offering high specific surface area, inherent capillary channels, and porosity, yet a systematic comparison of fiber types, structural designs, and performance benchmarks remains lacking. In this review, fiber-based SDIE materials are classified into synthetic fibers (including polymeric, carbon, glass, metal, and ceramic fibers) and natural fibers (derived from plant, animal, algae, and mineral sources). Each fiber category is reviewed with emphasis on material properties, structural design, and photothermal performance. Finally, a comparative analysis of natural and synthetic fibers is provided, emphasizing water evaporation rates, evaporation efficiency, and structural differences (2D or 3D). Furthermore, many fibrous materials have incorporated photothermal materials, such as MXene, MoS₂, polypyrrole, carbon nanotubes, and rGO, to enhance solar absorption and photothermal conversion. The reported evaporation rates typically range from 1.4 to 4.4 kg·m^-2·h^-1 under 1 sun illumination. Under outdoor conditions, a solar steam evaporator has reached a water production of 27.8 kg·m^-2·day^-1. Additionally, many studies reported water evaporation efficiencies above 90%, and some exceeded 100% when harnessing the surrounding environment as an energy source. Finally, the overview of the research process of fiber-based evaporators provides valuable insights into their future development, based on the findings and analysis.