Oxygen Reduction Reaction on Pt-Y/C Catalysts: Activity and Long-Term Stability Study

Autor(es)

da Silva, Gabriel Christiano ; Perez, Joelma

• Tipo de documento: Artigo Científico
• Fonte: Journal of the Brazilian Chemical Society; v. N/A, p. 11-pg., 2022-10-14.

Resumo

Pt-Y/C catalysts were prepared by a modified formic acid method and their structural characteristics and activity for oxygen reduction reaction (ORR) were evaluated. X-ray diffraction analysis showed that no alloy was formed between the metals and X-ray photoelectron spectroscopy (XPS) experiments showed that yttrium is presented as Y2O3, Y(OH)3 and Y -O -Pt species. CO stripping voltammetry and in situ X-ray absorption spectroscopy confirmed the interaction between Pt nanoparticles and yttrium species. The Pt-Y/C 7:3 material showed the higher specific activity (103 mu A cmPt-2) for ORR. Following repetitive potential cycling, the activity for the ORR of the Pt-Y/C 7:3 catalyst declined in a similar proportion to the Pt/C material. Transmission electron microscopy analysis after stability for both catalysts showed that Pt/C particle size slightly increased and that for Pt-Y/C 7:3 remained the same. XPS made in ultrathin catalyst layer, agreeing with energy-dispersive X-ray spectroscopy analysis, revealed that the intensities of the Y 3d peaks were suppressed relative to the initial one and that yttrium in the form of Y2O3 and Y(OH)3 were dissolved, while the species Y -O -Pt still remain in the catalyst, maintaining the higher activity. (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: 13/17549-5 - Estudo das variações das propriedades físico-químicas de catalisadores Pt-Nd/C e Pt-Nd-Sn/C para a eletro-oxidação de etanol.
• Beneficiário: Nathalia Abe Santos
• Modalidade de apoio: Bolsas no Brasil - Doutorado