Bioinspired recognition in metal-organic frameworks enabling precise sieving separation of fluorinated propylene and propane mixtures

Abstract

The separation of fluorinated propane/propylene mixtures remains a major challenge in the electronics industry. Inspired by biological ion channels with negatively charged inner walls that allow selective transport of cations, we presented a series of formic acid-based metal-organic frameworks (MFA) featuring biomimetic multi-hydrogen confined cavities. These MFA materials, especially the cobalt formate (CoFA), exhibit specific recognition of hexafluoropropylene (C3F6) while facilitating size exclusion of perfluoropropane (C3F8). The dual-functional adsorbent offers multiple binding sites to realize intelligent selective recognition of C3F6, as supported by theoretical calculations and in situ spectroscopic experiments. Mixed-gas breakthrough experiments validate the capability of CoFA to produce high-purity (>5 N) C3F8 in a single step. Importantly, the stability and cost-effective scalable synthesis of CoFA underscore its extraordinary potential for industrial C3F6/C3F8 separations. This bioinspired molecular recognition approach opens new avenues for the efficient purification of fluorinated electronic specialty gases.