Building high-performance mixed matrix membranes from stable COF colloids for CO2/N2 separation

Abstract

A “retardation & solvation” strategy was developed for synthesizing stable β-ketoenamine linked covalent organic framework (COF) colloids. Their mixed matrix membranes (MMMs) with Pebax-1657 matrix, exhibited exceptional gas separation performance with a CO2 permeability up to 322 Barrer and a CO2/N2 selectivity over 72.1. These represented improvements of 4.25 and 1.49-fold over the pristine Pebax-1657 membrane under identical conditions, closely approaching the 2019 Robeson upper boundary.