Research progress and prospect of covalent organic frameworks (COFs) and composites: From synthesis to application in water contaminants

With the rapid advancement of industrialization, the issue of water pollution posed a series of urgent challenges to environmental safety and public health, necessitating prompt solutions. Covalent organic frameworks (COFs) were a class of porous organic materials with robust covalent bonds. COFs were known for large surface area, high porosity, and excellent stability and selectivity for pollutant removal. Fabricated by combining COFs with various substances, these composites leverage ordered structures and ease of modification for expanded applications in pollution control. A detailed introduction to the classification methods of COFs and composites, and the nine common fabrication techniques were summarized. The advancements in research related to the adsorption and removal of heavy metals, organic pollutants, and radioactive nuclides by COFs and composites were presented. The mechanisms underlying the adsorption of pollutants in aquatic environments were explored, which provided novel perspectives on the utilization of COFs and modified materials for contaminant adsorption. Based on the aforementioned content, the current limitations of COFs and composites in removal of waterborne pollutants, as well as potential solutions, were summarized. Furthermore, promising prospects for the development in the field of pollutant adsorption were also outlined. The objective was to deepen the comprehension of COFs and COF-based composites, so as to promote the wider application of COFs and COF-based composites in the field of pollutant adsorption.