Abstract
The electronics industry necessitates highly selective adsorption separation of hexafluoropropylene (C(3)F(6)) from perfluoropropane (C(3)F(8)), which poses a challenge due to their similar physiochemical properties. In this work, we present a microporous flexible-robust metal-organic framework (Ca-tcpb) with thermoregulatory gate opening, a rare phenomenon that allows tunable sieving of C(3)F(8)/C(3)F(6). Remarkably, the temperature-dependent adsorption behavior enhances the discrimination between the larger C(3)F(8) and the smaller C(3)F(6), resulting in unprecedented C(3)F(6)/C(3)F(8) selectivity (over 10,000) compared to other well-known porous materials at an optimal temperature (298 K). Dynamic breakthrough experiments demonstrate that high-purity C(3)F(8) (over 99.999%) could be obtained from a C(3)F(6)/C(3)F(8) (10:90) mixture under ambient conditions. The unique attributes of this material encompass exceptional adsorption selectivity, remarkable structural stability, and outstanding separation performance, positioning it as a highly promising candidate for C(3)F(6)/C(3)F(8) separation. Single-crystal structural analysis of C(3)F(6)-loaded Ca-tcpb and theoretical calculations elucidate the host-guest interaction via multiple intermolecular interactions.