Microwave-Assisted Synthesis of Pt-Au Nanoparticles with Enhanced Electrocatalytic Activity for the Oxidation of Formic Acid

Autor(es)

Cabello, Gema ; Davoglio, Rogerio A. ; Hartl, Fabian W. ; Marco, Jose F. ; Pereira, Ernesto C. ; Biaggio, Sonia R. ; Varela, Hamilton ; Cuesta, Angel

• Tipo de documento: Artigo Científico
• Fonte: Electrochimica Acta; v. 224, p. 56-63, JAN 10 2017.
• Citações Web of Science: 21

Resumo

We report the microwave-assisted hydrothermal synthesis of bimetallic Pt-Au nanoparticles with different Pt/Au mole ratio, and investigate their performance towards the electro-oxidation of formic acid. The as-synthesized Pt-Au sol was dispersed on a graphite electrode, without any binding agents, which allowed us to control the mass of alloy deposited. Pt-Au alloys showed better activity than bulk Pt and/or Pt nanoparticles towards the oxidation of formic acid, as evidenced by the decrease in the onset potential and the higher currents in the corresponding cyclic voltammograms. The higher activity is due both to atomic-ensemble effects, which lead the reaction through the so-called direct pathway with insignificant CO poisoning, and to electronic effects, which optimised the interaction between the catalyst surface and the reactive intermediate in the direct path. Further insight into the individual contributions of atomic-ensemble and electronic effects and their effect on the catalytic activity was provided by the analysis of galvanostatic potential oscillations. (C) 2016 Elsevier Ltd. All rights reserved. (AU)

• Processo FAPESP: 13/16930-7 - Eletrocatálise V: processos eletrocatalíticos de interconversão entre as energias química e elétrica
• Beneficiário: Edson Antonio Ticianelli
• Modalidade de apoio: Auxílio à Pesquisa - Temático
• Processo FAPESP: 13/07296-2 - CDMF - Centro de Desenvolvimento de Materiais Funcionais
• Beneficiário: Elson Longo da Silva
• Modalidade de apoio: Auxílio à Pesquisa - Centros de Pesquisa, Inovação e Difusão - CEPIDs
• Processo FAPESP: 14/08030-9 - Eletrocatálise em regime oscilatório: espectroscopia IR in situ na configuração ATR-SEIRAS
• Beneficiário: Fabian Hartl
• Modalidade de apoio: Bolsas no Brasil - Doutorado Direto