Strong binding site molarity of MOFs and its effect on CO2 adsorption

Abstract

Metal organic frameworks (MOFs) with strong binding sites usually have remarkable CO2 adsorption capacity at ambient conditions. A new material parameter, the strong binding site molarity, defined as the number of the strong binding sites divided by the molecular weight of the unit cell of MOF, is introduced to understand CO2 adsorption on these MOFs. The CO2 adsorption capacity can be correlated to the strong binding site molarity in 1:1 ratio. The strong binding site coverage by CO2 molecules can also be correlated to the isosteric heat of CO2 adsorption at a given pressure. The strong binding site molarity is used to predict CO2 adsorption amount of several new types of MOFs to show its uses in selection or design of MOFs for CO2 capture.