The impact of CO₂ is a global issue and many scientists are looking into ways of CO₂ mitigation.  Materials that are capable of capturing and storing CO₂ are therefore of great importance and metal organic frameworks (MOFs) already show great promise for such applications.  

George Shimizu and colleagues from the University of Calgary, have therefore developed a porous, amine functionalised MOF that shows a high value for the heat adsorption of CO₂.  

The heat of adsorption - the amount of heat evolved during an adsorption - is a measure of the affinity of a gas for a material.  Therefore, the higher the heat of adsorption of a gas, the better the gas capture and storage capability of the material. 

In industry, amines are commonly used as scrubbers for CO₂.  Therefore, Shimizu's aim was to develop a material with amine groups lining the pores.  'In these materials, the size, shape and chemical functionalisation all contribute to the high affinity over the range of gas loading,' says Shimizu.

In the future Shimizu and his team hope to develop crystalline MOF sorbents with larger pores and higher loadings.  The high heat of adsorption seen in this research is a promising step forward.  Shimizu believes that gas separations based on selective sorption, brings the ultimate goals much closer.

Michael Brown