Recent advances in the synthesis of covalent organic framework-based membranes and their applications for liquid-based separation

Abstract

Membrane technology, as an efficient and eco-friendly separation means, has demonstrated substantial superiority in liquid-based separation and plays a pivotal role in environmental conservation and resource utilization. Traditional polymer-based membranes have long dominated the market for their simple preparation and low cost. But the disordered structure and irregular aperture of conventional amorphous membranes seriously hinder their performance. Recently, the emergence of covalent organic frameworks (COFs) has brought new vigor to membrane-based separation. COFs, connected by covalent bonds, have good crystallization and regular and uniform pore structure, thereby showcasing excellent stability and separation performance, becoming an ideal membrane material. In this paper, the synthesis and modification of COF-based membranes were reviewed, their inherent properties were also introduced. Besides, their applications in liquid-based separation were elaborated. Lastly, the challenges and focal points were discussed, aiming at offering inspirations for the development of COF-based membranes.