Metal-polyacrylic acid complex aerogels for efficient cycloaddition of CO2 with propylene oxide

Abstract

The cycloaddition reaction of carbon dioxide with propylene oxide captures considerable attention owing to its environmental friendliness, economy and 100% atomic utilization. Homogeneous metal catalysts exhibit excellent performance in cycloaddition reactions, but their widespread applications are limited by complicated preparation and recovery processes. It is important to develop effective strategies to immobilize homogeneous catalysts, and even immobilize active metal ions into solid carriers. Herein, we developed an innovative and universal strategy to immobilize metal ions through the complexation of metal ions with organic polymerization. The Zinc-manganese bifunctional polyacrylic acid complex (ZnMn-PAA) aerogels prepared using this strategy exhibited remarkable catalytic activity and stability in the cycloaddition reaction of carbon dioxide (CO2) and propylene oxide (PO). Mechanism studies revealed that the Zn and Mn central sites respectively enhanced the activation of PO and CO2, and the synergistic effect of bimetallic sites guaranteed to the excellent catalytic performance.