Evidence of pressure enhanced CO2 storage in ZIF-8 probed by FTIR spectroscopy.

Due to the large porosity and unique framework stability, ZIF-8, a representative zeolitic imidazolate based member of metal-organic framework (MOF) family exhibited excellent adsorption capacities for a wide range of gases, including greenhouse gases. Using in situ FTIR spectroscopy, ZIF-8 framework was investigated when loaded with CO2 in a diamond anvil cell at high pressures far beyond the conventional gas adsorption pressure. The IR profile of CO2 as well as the ZIF-8 shows direct evidence of the interactions between CO2 and ZIF-8, indicating enhanced storage of CO2 in the framework. In addition, the storage behavior was found to be strongly pressure dependent, and the interaction mechanism was explored. These findings demonstrated great potential in the greenhouse gases storage applications using MOF based materials.