| Texto completo | |
| Autor(es): |
Osmari, Taynara A.
;
Petrolini, Davi D.
;
Lopez-Castillo, Alejandro
;
de Morais, Leonardo Henrique
;
Zanchet, Daniela
;
Sainna, Mala A.
;
Willock, David
;
Gallo, Jean Marcel R.
;
dos Santos, Joao B. O.
;
Bueno, Jose Maria C.
Número total de Autores: 10
|
| Tipo de documento: | Artigo Científico |
| Fonte: | MATERIALS TODAY CHEMISTRY; v. 41, p. 10-pg., 2024-09-25. |
| Resumo | |
Copper (Cu) nanoparticles, widely utilized as catalysts in industrial applications, exhibit intriguing behavior in structure-sensitive reactions like ethanol dehydrogenation. Contrary to expectations, the catalytic activity does not consistently increase as the size of Cu nanoparticles decreases. In Cu catalysts, the particle size significantly effects the Cu-0/Cu+ ratio on the nanoparticle surface. Decreasing the size of Cu nanoparticles promotes their oxidation, leading to the formation of Cu+ and O2- species. This alteration subsequently influences the structural and electronic properties of the catalytic Cu sites. Through Cu nanoparticle calculations, the presence of an O ad-atom was identified to modify the electron density at the Cu site, thereby altering the ethanol adsorption energy and impacting the overall catalytic activity. The increase in O coverage, due to size effects, resulted in a notable decrease in the heat of adsorption on Cu nanoparticles (by approximately 20 kJ mol(- 1)). The observed high Delta E-ads indicates that more ethanol molecules could reach the transition state for the reaction, subsequently augmenting turnover rates (TOF) and reducing the apparent activation energy (E-aap) concerning Cu particle size. (AU) | |
| Processo FAPESP: | 18/01258-5 - Novos processos catalíticos e fotocatalíticos para a conversão direta de metano e CO2 em produtos |
| Beneficiário: | José Maria Correa Bueno |
| Modalidade de apoio: | Auxílio à Pesquisa - Temático |
| Processo FAPESP: | 23/18451-0 - Desenvolvimento de novo processo para oxidação direta de metano a metanol usando catalisadores de Cu- Zeolitas |
| Beneficiário: | Davi Domingos Petrolini |
| Modalidade de apoio: | Bolsas no Brasil - Pós-Doutorado |
| Processo FAPESP: | 19/12501-0 - Estudo teórico de sistemas bidimensionais |
| Beneficiário: | Alejandro López Castillo |
| Modalidade de apoio: | Auxílio à Pesquisa - Regular |
| Processo FAPESP: | 16/02128-2 - Desenvolvimento de novos sistemas catalíticos para a biorrefinaria |
| Beneficiário: | Jean Marcel Ribeiro Gallo |
| Modalidade de apoio: | Auxílio à Pesquisa - Jovens Pesquisadores |