Confinement of H2O and EtOH to enhance CO2 capture in MIL-53(Al)-TDC

Abstract

EtOH sorption properties were investigated in MIL-53(Al)-TDC and found a strong interaction between EtOH and the MOF material (ΔH_ads = 69.6 kJ mol⁻¹). CO₂ capture was enhanced upon confining small amounts of H₂O. Upon confining small amounts of EtOH however, the CO₂ uptake was not improved. The difference in CO₂ uptake with EtOH and H₂O was rationalised using computational calculations. The analysis of the quantum theory of atoms in molecules (QTAIM) showed a covalent interaction between a MOF model and confined molecules (EtOH and H₂O), and no difference in the hydrogen bonds between confined molecules and CO₂.