Hollow MOF capsule encapsulated amino-functionalized ionic liquid for excellent CO2 catalytic conversion

The engineering of highly efficient and stable heterogeneous catalysts for catalytic conversion of CO₂ to high value-added products is highly desirable but presents a great challenge. Herein, we reported the synthesis of a series of multifunctional IL@H-Zn/Co-ZIF composite catalysts with a unique porous hollow capsule structure and encapsulated amino-functionalized ionic liquids (ILs). The unique hollow capsule structure of IL@H-Zn/Co-ZIF provides sufficient space for loading active ILs (C₂NH₂Mim⁺]Br^-]) and fast mass transfer of substrate molecules during catalysis. Furthermore, the microporous Zn-ZIF shell can effectively avoid the leaching of active ILs. Benefiting from the unique hollow structure, the resultant IL@H-Zn/Co-ZIF demonstrated excellent catalytic performance (>95% yield), and good recyclability (still remained about 90% activities after 5 cycles) when applied in the CO₂ cycloaddition reaction under solvent and co-catalyst free conditions.