Amide-functionalized organic cationic polymers toward enhanced catalytic performance for conversion of CO2 into cyclic carbonates

作者：Wan, Ya-Li; Wang, Li; Wen, Lili^*

来源：Journal of CO2 Utilization, 2022, 64: 102174.

DOI：10.1016/j.jcou.2022.102174

• Bifunctional catalyst
• Hydrogen bond donor
• Amide group
• CO2
• Cyclic carbonates

Developing highly efficient, cost-effective and robust heterogeneous catalysts for carbon dioxide (CO2) fixation into valuable chemicals plays an essential role in carbon emissions reduction. Herein, a family of novel and bifunctional hypercrosslinked polymers, which consist of amide groups (-CONH-) as hydrogen bond donors (HBDs) and Br over line as nucleophiles, were developed for metal-and co-catalyst free cycloaddition of CO2 to epoxides. The incorporation of amide units into the polymeric networks not only provided active sites for synergistic activation of epoxides, but it also enhanced their swelling abilities toward epoxide substrates. As a result, the optimal catalyst exhibited high catalytic performance towards the cycloaddition of CO2 and epoxide to cyclic carbonate, the catalytic activity was comparable to those of the homogeneous analogues and outperformed most of the metal-free polymeric catalysts previously reported. Experimental and density functional theory (DFT) investigations suggested that excellent activity of the catalyst stemmed from the synergistic effect between amide HBDs and Br over line nucleophiles, as well as its excellent swelling ability toward epoxides. Additionally, the catalyst exhibited excellent structural stability and could be reused at least 10 times without significant activity loss. The present work not only highlights a versatile HBD to construct efficient and robust solid catalysts for CO2 fixation, but also paves the way to boost the performance of polymeric catalysts by engineering their swelling abilities toward reactant molecules.

• 单位
  中国科学院福建物质结构研究所