| Texto completo | |
| Autor(es): Mostrar menos - |
Ferreira, Rayse Machado
;
de Lima, Scarllett Lalesca Santos
;
Pereira, Fellipe dos Santos
;
Mouchrek, Charbel Nagib
;
Takana, Auro Atsushi
;
Domingues, Sergio Humberto
;
Fonsaca, Jessica Eliza Silva
;
Liu, Liying
;
Yatsuzuka, Rebeca
;
da Silva, Anderson Gabriel Marques
;
Aquino, Flavia de Medeiros
;
Garoia, Marco Aurelio Suller
Número total de Autores: 12
|
| Tipo de documento: | Artigo Científico |
| Fonte: | Applied Surface Science; v. 651, p. 11-pg., 2024-01-03. |
| Resumo | |
Oxygen Reduction Reaction (ORR) for clean energy is hindered by expensive Pt -based electrocatalysts, prompting efforts to replace it with alternative electrocatalysts. Thus, we started by synthesizing MnO2 nanowires through a hydrothermal approach, followed by the growth of ruthenium nanoparticles (Ru NPs) without surface modification, using just 2.0 wt% of the noble metal (MnO2-Ru). However, to further enhance the electrocatalyst's performance and reduce costs, we combined different ratios of reduced graphene oxide (rGO) with the electrocatalyst. X-ray photoelectron spectroscopy, scanning electron microscopy, transmission electron microscopy, and energy dispersive X-ray spectroscopy were employed to characterize the chemical composition and morphological properties of MnO2-Ru. These analyses identified the presence of the compounds during synthesis and confirmed the deposition of Ru NPs on the surface of MnO2 nanowires. The optimized MnO2-Ru/rGO demonstrated superior ORR activity than rGO, MnO2 , and MnO2-Ru individually, with more positive onset potential (-0.054 V) and half -wave potential of -0.173 V. Notably, MnO2-Ru/rGO reduced oxygen via the fourelectron transfer pathway. Furthermore, the higher stability and excellent methanol tolerance of MnO2-Ru/ rGO compared to the commercial 20 wt% Pt/C indicates its suitability for fuel cells, maintaining approximately 70 % of its initial current after 8000 s. (AU) | |
| Processo FAPESP: | 20/13288-6 - Materiais bidimensionais e seus derivados para biossensoriamento fotônico de patógenos |
| Beneficiário: | Jéssica Eliza Silva Fonsaca |
| Modalidade de apoio: | Bolsas no Brasil - Pós-Doutorado |