Simultaneous adsorption of SO₂ and CO₂ in an Ni(bdc)(ted)_0.5 metal–organic framework

The metal-organic framework Ni(bdc)(ted)0.5 is a promising material for simultaneous capture of harmful gases such as SO2 and CO2. We found that SO2 performs much better than CO2 during adsorption, and the lack of physical insight was clarified through detailed analyses of the electronic structures obtained from density functional theory calculations. Our results showed that strong interactions of the d band of Ni atoms with the valence states (2n, 3n, and 4n) of SO2 but almost not with those of CO2 are the main reasons. Our finding is useful for the rational design of new metal-organic frameworks with suitable interactions for the simultaneous capture of not only SO2 and CO2 but also other gases.