Synergistic effects between highly dispersed CuOx and the surface Cu-[Ox]-Ce structure on the catalysis of benzene combustion

• Published in: Journal of catalysis 2022-04, Vol.408, p.9-23
• Main Authors: Hou, Jiancai, Hu, Jiangliang, Chang, Liping, Wang, Jiancheng, Zeng, Zequan, Wu, Dongxia, Cui, Xinmin, Bao, Weiren, Yao, Junxuan
• Format: Article
• Language: English
• Subjects: Adsorption sites; Benzene combustion; Cu-Ce mixed oxide; CuOx cluster; Synergistic effect
• ISSN: 0021-9517
• DOI: 10.1016/j.jcat.2022.02.012

[Display omitted] •Cu-Ce mixed oxides with four-type copper species was prepared by sol–gel method.•Roles of CuOx cluster, Cu-[Ox]-Ce structure and synergistic effects were revealed.•Copper species were demonstrated not the adsorption sites for benzene.•The evolution of oxygen vacancies and oxygenated intermediates were analyzed. Cu-Ce mixed oxides with different Cu contents were synthesized through a sol–gel method, after which their effect on benzene combustion catalysis was evaluated. CeCu0.50 calcined at 300 °C (CeCu0.50–300) exhibited a high areal rate [2.0 × 10−6 mol/(m2 h)] and turnover frequency (0.16 s−1) at 170 °C, thus demonstrating the strong synergistic effect between CuO and CeO2. The catalyst durability and influence of H2O(g) on catalytic activity were also investigated. Correlation analyses between the catalytic activities and the amount of copper species, indicated that CuOx clusters and the Cu-[Ox]-Ce structure were the main active sites and bridge for oxygen transfer, respectively. Furthermore, benzene did not adsorb onto the copper species. The effect of temperatures on surface oxygen vacancies and oxygenated intermediates were also evaluated. Taken together, our findings provided key insights into the synergistic effects of different copper species on benzene combustion.