Aniline-Based Hyper-Cross-Linked Polymer–In₂O₃ Composite Boosting CO₂ Epoxide Ring-Opening Reaction Activity without Cocatalysts

Abstract

Significant efforts have been devoted to develop an efficient catalytic system without the use of cocatalysts for the conversion of CO 2 to cyclocarbonate. However, the low CO 2 adsorption on the surfaces of catalysts is generally attributed to their low specific surface area and thermodynamic stability. Herein, we report on the efficacy of a composite heterogeneous catalyst prepared by coating the In 2 O 3 surface with aniline-based polymers and subsequent coordination with hydrogen-bond donating functional groups (HBD). This composite shows high catalytic performance for CO 2 epoxide ring-opening reactions (99%) and excellent recycling performance (sixth run) under mild conditions without the need for cocatalysts. In contrast, the catalytic performance of In 2 O 3 without a polymer coating is significantly reduced. This study presents a feasible strategy on building HBD sites into CO 2 -adsorptive polymercoated In 2 O 3 surface and realizing CO 2 cycloaddition reaction in an aerobic environment.