Uniform Core-Shell Microspheres of SiO 2 @MOF for CO 2 Cycloaddition Reactions.

A SiO 2 @MOF core-shell microsphere for environmentally friendly applications was introduced in this study. Several types of metal-organic framework core-shell microspheres were successfully synthesized. To achieve high stability and favorable catalytic performance, modification and coating methods were necessary for optimization. The improved SiO 2 @MOF core-shell microspheres were used in the cycloaddition reaction of carbon dioxide and propylene oxide. Dispersion ability was enhanced by the addition of core-shell microspheres, which also produced high catalytic activity. Accompanied with tetrabutylammonium bromide as a co-catalyst, SiO 2 @ZIF-67 had a maximum conversion of 97%, and the results revealed that SiO 2 @ZIF-67 could be used for 5 reaction cycles while maintaining high catalytic performance. This recycling catalyst was also reacted with a series of terminal epoxides to form corresponding cyclic carbonates with high conversion rates, indicating that SiO 2 @MOF core-shell microspheres exhibit promise in the field of catalysis.