丙烷
催化作用
吸附
活动站点
氧气
无机化学
化学
有机化学
作者
Chu-Feng Liu,Xufang Wang,Cai-Hao Wen,Bei Li,Cen Tang,Ji-Qing Lu,Ming Luo,Jian Chen
标识
DOI:10.1016/j.apsusc.2023.156572
摘要
Identifying active sites is critical for rational catalyst design. We clarified the surface active sites for propane and CO oxidation over Co3O4-based catalysts using probe reactions of propane and CO oxidation, respectively. In comparison to Co3O4/ZSM-5, Co3O4/CeO2 has superior CO oxidation activity but inferior propane oxidation activity. CeO2 oxygen vacancies promote O2 activation, the rate-determined step (RSD) for CO oxidation, and avoid competitive adsorption of O2 and CO on Co3O4 species, resulting in superior CO oxidation activity on Co3O4/CeO2. Whereas the RSD for propane oxidation is synergistic catalysis of Co3O4 species and acid sites, Co3O4/ZSM-5 exhibits improved propane oxidation activity as a result of the abundant acid sites from ZSM-5. Due to a lack of oxygen vacancies for O2 activation, competitive adsorption of O2 with propane or CO on Co3O4 species is observed on Co3O4/ZSM-5. Furthermore, surface Co3+ species in Co3O4 are discovered to be active sites for both CO and propane activation. As a result of the increased surface Co3+ species, the pre-reduced and post-oxidized Co3O4 catalysts (Co3O4/ZSM-5-A and Co3O4/CeO2-A) exhibit improved activity for both propane and CO oxidation.
科研通智能强力驱动
Strongly Powered by AbleSci AI