Reverse synthesis of yolk–shell metal–organic frameworks

We report the first examples of yolk-shell metal-organic framework (MOF) heterostructures based on topologically distinct MOFs: ZIF-8/ZIF-67 and UiO-66. This was accomplished through an innovative reverse synthesis strategy: A hollow UiO-66 was first constructed; the precusors of the ZIFs were then loaded into the cavity of hollow UiO-66 through a mixed solvent impregnation method; subsequent crystallization under solvothermal condition led to the formation of yolk-shell MOFs containing one or multiple ZIF particles confined within a chemically robust single crystalline UiO-66 shell.