A New Route to Porous Metal-Organic Framework Crystal-Glass Composites

Metal-organic framework crystal-glass composite (MOF-CGC) materials consist of a crystalline MOF embedded within a MOF-glass matrix. In this work, a new synthetic route to these materials is demonstrated through the preparation of two ZIF-62 glass-based CGCs, one with crystalline ZIF-67 and the other with crystalline UiO-66. Previous attempts to form these CGCs failed due to the high processing temperatures involved in heating above the melting point of ZIF-62. Annealing of the ZIF-62 glass above the glass transition with each MOF however leads to stable CGC formation, at lower temperatures. The reduction in processing temperatures will enable the formation of a greatly expanded range of MOF-CGCs.