Metal-organic framework/graphene oxide composites for CO2 capture by microwave swing adsorption

Metal-organic frameworks (MOFs)/graphene oxide (GO) composites are of growing interest due to their properties which can exceed those of the pure components, including post combustion CO2capture. Series of composites suitable for CO2capture under flue gas conditions based on the microporous water stable MIL-91(Ti) have been prepared with different GO contents, following two routes, in situ and post-synthetic. It was observed that the 5 wt% GO in situ composite exhibits a semi-conducting behavior, while the post-synthetic materials are insulating, even with high (20 wt%) GO content. As a consequence, this composite absorbs microwave radiation more efficiently compared to the pure MOF and post-synthetic materials. Finally, we report that CO2desorption is much faster under microwave irradiation compared to direct electric heating on MOF/GO in situ materials, paving the way for future energy-saving microwave swing adsorption processes.