Molecular Sieving Properties of Nanoporous Mixed-Linker ZIF-62: Associated Structural Changes upon Gas Adsorption Application

The evaluation of the flexibility in zeolitic imidazolate frameworks (ZIFs) has been very useful to understand their performance gas adsorption and separation applications. Here, we have evaluated properties a nanoporous mixed-linker ZIF-62 using combination measurements, grand canonical Monte Carlo simulations, synchrotron X-ray powder diffraction under operando conditions. While studies at 77 K atmospheric pressure predict large O2/N2 ability, computational anticipate that observed differences must be attributed kinetic restrictions N2 access internal porosity cryogenic temperatures. Interestingly, upon small increase temperature (90 vs K), both O2 are able inner porous structure through promotion phase transition (ca. 3.8% volume expansion) adsorption. This narrow (np) expanded (ep) structural is completely suppressed above 150 K. Based on excellent molecular sieve for temperatures, extended our study linear branched hydrocarbons. predicts preferential alkanes over alkenes hydrocarbons (C2), while case C3 above, process mainly defined by restrictions.