VICTORIA AMATHEUS MAIA

Projetos de Pesquisa
Unidades Organizacionais
Cargo

Filtros

20242
Limpar filtros

Configurações

Tem arquivos: true × Assunto: voltametry ×

Resultados de Busca

Agora exibindo 1 - 2 de 2
  • Imagem de Miniatura
    Artigo IPEN-doc 30430
    Optimizing PtSn composition in direct sugarcane extract fuel cells
    2024 - VILLARDI, BRUNO D.Q.; MAIA, VICTORIA A.; NANDENHA, JULIO; ZAMBIAZI, PRISCILLA J.; SOUZA, RODRIGO F.B. de; NETO, ALMIR O.
    Pt90Sn10/C composition exhibited a strong maximum power density value and a good sugar oxidation response in sugar extract solution in comparison with others electrocatalysts prepared. Pt90Sn10/C demonstrated a maximum power density approximately 93% higher than that of Pt80Sn20/C, which is the second most active material and more than 8 times bigger than Pt/C. The primary difference between the two lies in glucose consumption, which is approximately 90% higher in Pt90Sn10/C. It is important to highlight that in the more active materials; fructose consumption remains relatively constant, ranging between 7 and 8%. The enhanced performance could be attributed to both the altered electronic properties resulting from tin integration into the platinum crystal lattice and the activation of water at less positive potentials by a bifunctional mechanism. XRD results showed that the lattice parameters were expanded indicating the insertion of Sn to Pt, while that cyclic voltammetry showed that all materials present the hydrogen adsorption–desorption region over Pt (− 0.2 to 0.15 V); however, when increasing the tin content in the catalyst, the region decreases the definition and is associated with the presence of transition metals such as Sn. TEM images and histograms for PtSn showed the increase in the average particle size accompanying the tin enrichment in the composition; this effect could be tin oxide in material surface and is in agreement with other works.
  • Imagem de Miniatura
    Artigo IPEN-doc 30416
    Innovative lead-carbon battery utilizing electrode-electrolyte assembly inspired by PEM-FC architecture
    2024 - SOUZA, RODRIGO F.B. de; SILVESTRIN, GABRIEL A.; CONCEICAO, FELIPE G. da; MAIA, VICTORIA A.; OTUBO, LARISSA; NETO, ALMIR O.; SOARES, EDSON P.
    This study explores the innovative integration of a lead‑carbon battery with an electrode-electrolyte assembly inspired by Proton Exchange Membrane Fuel Cell (PEM-FC) architecture. The lead‑carbon material, synthesized with a 40 % mass ratio using the Flash Joule Heating Method, exhibits predominant Pb0 and PbO phases, as observed in lattice parameter fringes, with additional detection of the PbO2 phase. The resulting Carbon-Lead Acid Battery (CLAB) demonstrates a specific capacity of 11.2 mAh g−1. The incorporation of carbon enhances nanoparticle stability, yielding a highly stable battery performance over 100 cycles, with discharge potential variations of <2 %. This innovative CLAB assembly not only showcases stable performance and also introduces the potential for constructing flexible lead batteries, expanding technological applications. The study provides comprehensive insights into the synthesis, performance, and prospects of this novel lead‑carbon battery architecture, emphasizing its significance in the realm of energy storage solutions.