Surface activated zinc-glutarate for the copolymerization of CO₂ and epoxides

Zinc-glutarate (ZnGA) is a promising catalyst that can form polymers from CO₂ and epoxides, thereby contributing to the development of CO₂ utilization technologies and future sustainability. One of the obstacles to commercializing ZnGA in polymer industries is its low catalytic activity. In this study, we introduced activated two-dimensional (2D) ZnGA to improve its catalytic activity in polymerization. The morphology-controlled 2D ZnGA was treated with H₃Co(CN)₆, and a porous granular-type Co-modified ZnGA (Co-ZnGA) was prepared. The morphology of 2D ZnGA is a prerequisite for the activation by H₃Co(CN)₆. The catalytic properties of Co-ZnGA were evaluated by copolymerization of various epoxides and CO₂, and exhibited catalytic activity of 855, 1540, 1190, and 148 g g-cat^-1 with propylene oxide, 1,2-epoxyhexane, 1,2-epoxybutane, and styrene oxide, respectively. This study provided a new strategy using 2D ZnGA instead of conventional ZnGA for increasing the catalytic activity in CO₂ polymerization.