Abstract
• 5-coordinated Li was observed in Li/MgO catalysts with 7 Li NMR for the first time. • Li/MgO catalysts with the same Li concentration have different OCM performances. Such differences are correlated to 5-coordinated Li ions thus oxygen vacancies. • A higher concentration of oxygen vacancy leads to a higher C 2 selectivity. The role of Li and the mechanism in the Li/MgO catalyzed oxidative coupling of methane (OCM) are still under debate. Two Li/MgO catalysts with similar Li concentrations but very different catalytic performances in OCM reactions were studied by using 7 Li NMR spectroscopy. 5-coordinated Li ions are present after the catalysts are calcined in air, activated in O 2 and used for OCM reaction, and their relative concentrations differ significantly in the two catalysts. Such changes can be ascribed to different numbers of oxygen vacancies, leading to distinct catalytic properties for the two Li/MgO catalysts.
Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
