Regulating C₂H₂ and CO₂ Storage and Separation through Pore Environment Modification in a Microporous Ni-MOF

Abstract

The storage and separation of C2H2 and CO2 require specific porous materials having surfaces onto which C2H2 or CO2 molecular can be selectively adsorbed. Through the modification of a multifunctional ligand with −F, −Cl, −NH2, −CH3, −OCH3, and inorganic secondary building units (SBUs) with bipy-N ligands (dimethylamine, pyridine, 4-aminopyridine, and isonicotinic acid) based on a microporous Ni-MOF, the pore environment optimization is realized, achieving the enhancement of the adsorption and separation performances of C2H2 and CO2. The C2H2 uptakes vary from 178.4 to 130.1 cm3 g–1 and CO2 from 83.8 to 44.6 cm3 g–1 at 273 K and 1 atm. The 4-aminopyridine and dimethylamine modified UPC-110 has the highest C2H2/CO2 separation selectivity (5.1), further supported and explained via Grand Canonical Monte Carlo (GCMC) simulation and breakthrough experiments. Our work not only provides new porous materials for efficient C2H2 and CO2 storage but also contributes to the strategy on improving gas adsorption and separation properties through pore environment modification.