Synergistic catalysis of mesoporous Cu/Co3O4 and surface oxygen vacancy for CO2 fixation to carbamates

• Published in: Journal of catalysis Vol. 418; pp. 178 - 189
• Main Authors: Zhou, Jiamin, Yang, Shengwen, Wan, Weihao, Chen, Limin, Chen, Jinzhu
• Format: Journal Article
• Language: English
• Published: Elsevier Inc 01.02.2023
• Subjects: Carbamate; Carbon dioxide; Copper; Oxygen vacancy; Synergistic effect; Synergistic effect; Copper; Carbamate; Carbon dioxide; Oxygen vacancy
• ISSN: 0021-9517; 1090-2694
• DOI: 10.1016/j.jcat.2023.01.017

Cu-doped Co3O4 exhibits a synergistic catalysis between metallic Cu and surface oxygen vacancy for CO2 transformation into oxazolidinone and β-oxopropylcarbamate. [Display omitted] •Cu and surface OV synergistically catalyze CO2 transformation into carbamate.•Doped Cu in Cu/Co3O4 enhances surface OV/acidity promoting rate-determining step.•Carbamate formation rate and surface acidity of Cu/Co3O4 increase with surface OV.•Both oxazolidinone and oxopropylcarbamate are obtained from CO2 via OV catalysis. As one of the most important defects, oxygen vacancy (OV) on the surface of transition metal oxides can function as catalytic reactive site for various reactions. Herein, Cu-doped Co3O4 (Cu/Co3O4) catalyst with rich surface OV was developed for efficient and quantitative transformations of CO2, primary amines, and propargyl alcohols to oxazolidinones at mild reaction conditions. Both initial formation rate of oxazolidinone and surface acidity on the Cu/Co3O4 increased with its surface OV concentration. The doped Cu species in Cu/Co3O4 functioned as an active site for propargyl alcohol activation, enhanced the surface OV concentration for CO2 activation, and improved the surface acidity to promote the rate-determining step in CO2-to-oxazolidinone transformation. In addition to oxazolidinones, Cu/Co3O4 was applicable to various β-oxopropylcarbamates syntheses by coupling CO2, propargyl alcohols and secondary amines. This research demonstrates a synergistic cooperative catalysis between Cu and surface OV for CO2 transformation to high-valuable N-containing chemicals.