| Texto completo | |
| Autor(es): |
Destro, Priscila
;
Cantaneo, Daniel Augusto
;
Meira, Debora M.
;
Honorio, Guilherme dos Santos
;
da Costa, Luelc Souza
;
Bueno, Jose Maria C.
;
Zanchet, Daniela
Número total de Autores: 7
|
| Tipo de documento: | Artigo Científico |
| Fonte: | European Journal of Inorganic Chemistry; v. N/A, n. 33, p. 8-pg., 2018-09-09. |
| Resumo | |
Advanced studies of the formation and growth processes of metal alloy nanoparticles are of great importance and provide a better understanding for the fine tuning of their properties for the desired applications. In this work, we followed the synthesis of Au1-xCux colloidal nanoparticles by in situ time-resolved X-ray absorption fine structure (XAFS) spectroscopy. The particles were synthesized by a one-pot approach with a homemade reactor adapted to the XAFS measurements. The colloidal nanoparticles were also characterized by complementary ex situ techniques. Analyses at the Cu-K edge and Au-L-3 edge confirmed that the initial reduction of the Au species occurs at low temperatures (<100 degrees C) to form Au seeds that are subsequently enriched with Cu to form Au0.75Cu0.25 alloy nanoparticles at 225 degrees C. An important finding was the temporary formation of a Cu2O-type phase during the colloidal synthesis. This phase was consumed with the concomitant formation of the Au1-xCux alloy nanoparticles. These results directly confirm the previous proposal that the alloy formation occurs through a digestive-ripening-like process of an amorphous Cu-enriched phase. (AU) | |
| Processo FAPESP: | 11/50727-9 - Desenvolvimento de sistemas para produção de hidrogênio e para geração e utilização de energia eletro-química |
| Beneficiário: | Ernesto Rafael Gonzalez |
| Modalidade de apoio: | Auxílio à Pesquisa - Temático |
| Processo FAPESP: | 10/52291-0 - Compreensao das propriedades estruturais e de superficie de catalisadores de platina promovidos com cerio atraves de tecnicas de caracterizacao in situ sob a reacao de deslocamento gas-agua |
| Beneficiário: | Débora Motta Meira |
| Modalidade de apoio: | Bolsas no Brasil - Doutorado |