Researchers at PNNL have developed an electrochemical cell that utilizes MOF-based redox couples.  In this fashion, half-cells may be constructed with voltage applied so as to maintain the metal in the MOF at the desired +2 or +3 oxidation state.  By allowing the MOF to absorb CO2, the CO2 may then be selectively released by changing the voltage and hence oxidation state of the metal center.  Other gases may be amenable to similar selective absorption and release.