2, Lawrence Berkeley National Laboratory, Berkeley, California, United States
3, Mosaic Materials, Inc., Berkeley, California, United States
4, Harvard University, Cambridge, Massachusetts, United States
5, University of Delaware, Newark, Delaware, United States
6, The University of Texas at Austin, Austin, California, United States
Owing to their high surface areas, tunable pore dimensions, and adjustable surface functionality, metal-organic frameworks (MOFs) can offer advantages for a variety of gas storage and gas separation applications. In an effort to help curb greenhouse gas emissions from power plants, we are developing new MOFs for use as solid adsorbents in post- and pre-combustion CO2 capture, and for the separation of O2 from air, as required for oxy-fuel combustion. In particular, MOFs with diamine-functionalized metal sites are demonstrated to operate via an unprecedented cooperative insertion mechanism, leading to high selectivities and working capacities for the adsorption of CO2 over N2 under flue gas conditions. Multicomponent adsorption measurements further show these compounds to be effective in the presence of water, while calorimetry and temperature swing cycling data reveal low regeneration temperatures compared to aqueous amine solutions. In addition, a new spin transition mechanism will be elaborated as a means of achieving cooperative CO adsorption.