Ab Initio Investigation of CH4 Dehydrogenation on a (CeO2)(10) Cluster

Author(s)

Perac, Carina S. T. ; Andriani, Karla F. ; Piotrowski, Mauricio J. ; Da Silva, Juarez L. F.

• Document type: Journal article
• Source: Journal of Physical Chemistry C; v. N/A, p. 12-pg., 2022-07-15.

Abstract

We report a theoretical investigation of the activation and dehydrogenation of CH4 on a (CeO2)(10) cluster based on density functional theory calculations combined with the unity bond index-quadratic exponential potential approach. As expected, we identified a physisorption interaction mechanism between the CH4 and (CeO2)10 systems. Along the dehydrogenation, the interaction CHn-(CeO2)(10) occurs by chemisorption via the formation of C-O and H-O bonds. Due to adsorption effects, the oxidation state of Ce atoms changes from Ce4+ to Ce3+, which results in the elongation of the Ce-O bonds due to the larger radius of the Ce3+ species, and hence, it affects the formation of the CO and CH3OH species. Our combined approach showed that the first dehydrogenation step involves a transition-state formation induced by the molecular hybridization before the CH3 radical formation. Finally, our results indicate trends for new compound formation, once the energy barrier involved in the first step of dehydrogenation is overcome. (AU)

• FAPESP's process: 19/05561-7 - A Multiscale Framework Applied to the Investigation of CO2 Reduction on Metallic Nanoparticles: The Role of Size and Adsorbate Coverage Effects
• Grantee: Lucas Garcia Verga
• Support Opportunities: Scholarships in Brazil - Post-Doctoral
• FAPESP's process: 17/11631-2 - CINE: computational materials design based on atomistic simulations, meso-scale, multi-physics, and artificial intelligence for energy applications
• Grantee: Juarez Lopes Ferreira da Silva
• Support Opportunities: Research Grants - Research Centers in Engineering Program
• FAPESP's process: 21/03357-3 - Computational study of methane conversion in new products using cerium oxide-based catalysts
• Grantee: Carina de Souza Teixeira Peraça
• Support Opportunities: Scholarships in Brazil - Doctorate
• FAPESP's process: 18/21401-7 - Multi-User Equipment approved in grant 2017/11631-2: cluster computational de alto desempenho - ENIAC
• Grantee: Juarez Lopes Ferreira da Silva
• Support Opportunities: Multi-user Equipment Program
• FAPESP's process: 18/11152-0 - Catalyst design for direct conversion of methane to methanol: an ab initio Density Functional Theory investigation
• Grantee: Karla Furtado Andriani
• Support Opportunities: Scholarships in Brazil - Post-Doctoral