Research progress on the fabrication and application of lignin-based superhydrophobic composites

Superhydrophobic materials are widely used in multiple fields due to their unique surface properties. However, traditional superhydrophobic materials have problems such as high cost and poor environmental friendliness. Lignin, a natural polymer with abundant reserves, environmental friendliness, and renewability, is an ideal raw material for preparing superhydrophobic materials. This article reviews the research progress of lignin-based superhydrophobic materials. Firstly, the structure and properties of lignin are introduced. Its complex structure endows it with characteristics such as high reactivity, laying the foundation for the preparation of superhydrophobic materials. Secondly, the main strategies for the preparation of such materials are summarized, including methods such as chemical modification of lignin, micro-nano-sizing, and compounding with other materials. Finally, the application progress of this material in fields such as waterproof coatings, self-cleaning surfaces, seawater desalination, and oil-water separation is sorted out. Furthermore, the existing problems and challenges in the current research of this material, as well as the directions for future in-depth research are proposed, in the hope of promoting the development and sustainable application of lignin-based superhydrophobic materials.