Construction of the Co<sub>3</sub>O<sub>4</sub>/Nb<sub>2</sub>O<sub>5</sub> Composite Catalyst with a Prickly Spherelike Architecture for CO<sub>2</sub> Cycloaddition with Styrene Oxide
Jiangyong Liu, Bin Zhang
Abstract
A high-performance Nb 2 O 5 -based catalyst for the cycloaddition of CO 2 with SO is designed by properly unifying the concepts of compositional regulation and architectural engineering. The Co 3 O 4 /Nb 2 O 5 composite catalyst shows an intriguing prickly spherelike morphology. It exhibits a high styrene carbonate (SC) yield of 94.3% within 4 h (0.0824 mol g –1 h –1 ) under mild reaction conditions (0.4 MPa of CO 2 and a reaction temperature of 90 °C) assisted by tetrabutylammonium bromide (TBAB). The coupling of Co 3 O 4, which chemically interacts with Nb 2 O 5, can effectively modulate the electronic structures of Nb 2 O 5, constructing abundant acid/base sites for effectively activating the reactants and boosting the intrinsic activity. The high activity, cost-effectiveness, and good recyclability make the tailor-made Co 3 O 4 /Nb 2 O 5 prickly spheres more appealing for commercial applications. This work offers new insights into designing and constructing well-integrated metal oxide composites for the cycloaddition of CO 2 with an epoxide.