ole of quantum-size effects in the dehydrogenation of CH4 on 3d TMn clusters: DFT calculations combined with data minin

Autor(es)

Andriani, Karla F. ^[1] ; Felicio-Sousa, Priscilla ^[1] ; Morais, Felipe Orlando ^[2] ; Da Silva, Juarez L. F. ^[1]

Afiliação do(s) autor(es)

^[1] Univ Sao Paulo, Sao Carlos Inst Chem, POB 780, BR-13560970 Sao Carlos, SP - Brazil

^[2] Univ Sao Paulo, Sao Carlos Inst Phys, POB 400, BR-13566590 Sao Carlos, SP - Brazil

• Tipo de documento: Artigo Científico
• Fonte: CATALYSIS SCIENCE & TECHNOLOGY; v. 12, n. 3 DEC 2021.
• Citações Web of Science: 0

Resumo

In this work, we report a theoretical investigation of the role of quantum-size effects (QSEs) in the dehydrogenation of methane (CH4) on 3d transition-metal clusters, TMn, where TM = Fe, Co, Ni, and Cu, and n = 4-15. Our calculations were based on density functional theory combined with the unity bond index-quadratic exponential potential (UBI-QEP) approach and data mining (Spearman rank correlation, clustering). We found via clustering techniques that QSEs or the chemical species, TMs, do not affect the adsorption modes (geometric orientation of the molecules) of CH4, CH3, CH3 + H, and H on the TMn clusters. However, QSEs play a crucial role in modulating the magnitude of the adsorption energy, reaction energy, dissociation energy, and activation energy, in particular, for Cu-n clusters due to the unpaired electron for clusters with an odd number of electrons. Through the UBI-QEP approach, we found small activation energy barriers for small Fe-n clusters and larger ones for Ni-n clusters, i.e., QSEs can be explored to tune energy barriers. These findings are supported by Spearman analysis; however, we could not identify a general trend due to the quantum-size effects that correlate activation energy with the adsorption and dissociation energies for the studied systems. (AU)

• Processo FAPESP: 18/21401-7 - EMU concedido no processo 2017/11631-2: cluster computacional de alto desempenho - ENIAC
• Beneficiário: Juarez Lopes Ferreira da Silva
• Modalidade de apoio: Auxílio à Pesquisa - Programa Equipamentos Multiusuários
• Processo FAPESP: 18/11152-0 - Desenvolvimento de catalisadores para conversão direta de metano em metanol: uma investigação ab initio utilizando a da Teoria Funcional da Densidade
• Beneficiário: Karla Furtado Andriani
• Modalidade de apoio: Bolsas no Brasil - Pós-Doutorado