Thermodynamic analysis of gate-opening carbon dioxide adsorption behavior of metal-organic frameworks.

Thermodynamic analysis of gate-opening carbon dioxide (CO2) adsorption behavior of metal-organic frameworks (MOFs) was investigated using differential scanning calorimetry (DSC). Unlike measurements under nitrogen atmosphere, obvious exothermic and endothermic peaks were observed in DSC curves under CO2 flow. In situ heating X-ray diffraction and thermogravimetric analyses under CO2 revealed that reversible crystal structure and weight changes occurred upon CO2 adsorption/desorption. The thermodynamic parameters of the CO2 adsorption process by MOFs were determined by DSC analysis at various CO2 partial pressures.