Discovering Dinuclear Dioxygen-Bridged Cobalt(III) Complexes for Selective Binding of O2 from Air

The design and development of dioxygen activation in porous crystalline materials is a useful avenue for exploring selective adsorption of O2 that shows significant potential to enable separations of O2 and N2 from air. Porous materials featuring redox-active metal centers have received attention regarding selective O2 adsorption via chemisorption. Drawing inspiration from a dinuclear cobalt material ([(Co(III)2(bpbp)O2)2bdc](PF6)4 (CSD code: GAMVIB; bpbp– = 2,6-bis(N,N-bis(2-pyridylmethyl)aminomethyl)-4-tert-butylphenolato; bdc2– = 1,4-benzenedicarboxylato)) that displays reversible and selective O2 adsorption, we focus on searching for potential O2-selective materials with dinuclear cobalt clusters that have dioxygen-bridged Co(III) complexes. We combine structure screening with a high-level hybrid periodic density functional theory (DFT) workflow to investigate O2 and N2 adsorption in materials from validated crystal structure databases (e.g., the CSD database). These calculations identify multiple materials that are predicted to have superior O2 binding capability relative to GAMVIB. Grand Canonical Monte Carlo (GCMC) simulations based on DFT-developed force fields were performed for selected candidates to estimate the adsorption performance for O2/N2 mixtures.