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 O-2 that shows significant potential to enable separations of O-2 and N-2 from air. Porous materials featuring redox-active metal centers have received attention regarding selective O-2 adsorption via chemisorption. Drawing inspiration from a dinuclear cobalt material ([(Co(III)(2)(bpbp)O-2)(2)bdc](PF6)(4) (CSD code: GAMVIB; bpbp(-) = 2,6-bis(N,N-bis(2-pyridylmethyl)aminomethyl)-4-tert-butylphenolato; bdc(2-) = 1,4-benzenedicarboxylato)) that displays reversible and selective O-2 adsorption, we focus on searching for potential O-2-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 O-2 and N-2 adsorption in materials from validated crystal structure databases (e.g., the CSD database). These calculations identify multiple materials that are predicted to have superior O-2 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 O-2/N-2 mixtures.