Free-standing covalent organic framework films prepared via alternating deposition: structural analysis and CO₂ separation performances

Abstract

Covalent organic frameworks (COF) are a relatively new organic material group with periodically distributed pores. We developed a new method to prepare COF films from the gas phase by using “alternating deposition”. From High-resolution scanning transmission microscope images, we found a randomly oriented network structure in a high-temperature annealed (HTA) COF film. We also examined that the HTA-COF film had greater permeance of CO₂ than that of N₂ by the factor of 4.6.