Exploring the Performance Improvement for CO Chemical Fixation in Zn/ZnMg-MOFs.

A new 3D zinc-based metal-organic framework {[ZnL(DMF)(HO)(OH)]·5DMF} () (HL = 5,5',5″-(methylsilanetriyl) triisophthalic acid) was constructed with an organosilicon-based linker, where HL is a tetrahedral structure furnished with rich -COO chelating sites for Zn(II) immobilization. Compound exhibited two types of irregular one-dimensional channels and a three-dimensional skeleton with large specific surface area, making it a promising catalytic platform. Moreover, by incorporation of the second metal ion into the inorganic node of framework , isomorphic bimetallic MOF ZnMg- was successfully synthesized. ZnMg- demonstrated enhanced catalytic activity compared to under identical conditions. Contrast experiments and theoretical calculations indicate that bimetallic active sites play a facilitating role in the chemical fixation of epoxides and CO. It indicated that efficient chemical fixation of CO to cyclic carbonates was obtained over isomorphic MOF catalysts and ZnMg-.