Hollow Zn/Co ZIF Particles Derived from Core-Shell ZIF-67[at]ZIF-8 as Selective Catalyst for the Semi-Hydrogenation of Acetylene

The rational design of metal-organic frameworks (MOFs) with hollow features and tunable porosity at the nanoscale can enhance their intrinsic properties and stimulates increasing attentions. In this Communication, we demonstrate that methanol can affect the coordination mode of ZIF-67 in the presence of Co super(2+) and induces a mild phase transformation under solvothermal conditions. By applying this transformation process to the ZIF-67[at]ZIF-8 core-shell structures, a well-defined hollow Zn/Co ZIF rhombic dodecahedron can be obtained. The manufacturing of hollow MOFs enables us to prepare a noblemetal[at]MOF yolk-shell composite with controlled spatial distribution and morphology. The enhanced gas storage and porous confinement that originate from the hollow interior and coating of ZIF-8 confers this unique catalyst with superior activity and selectivity toward the semi-hydrogenation of acetylene. A mild phase transformation of ZIF-67[at]ZIF-8 core-shell structures is achieved under solvothermal conditions to generate unique hollow Zn/Co ZIF particles, which were used to generate Pd[at]MOF yolk-shell composites. They exhibit enhanced gas storage and high catalytic activity and selectivity in the semi-hydrogenation of acetylene.