Influence of Substrate Steps on the Catalytic Properties of Pt Layers: The Ethanol Electrooxidation Reaction

Autor(es)

Prieto, Mauricio J. ^[1] ; Tremiliosi-Filho, Germano ^[2]

Afiliação do(s) autor(es)

^[1] Univ Estadual Campinas, Inst Fis Gleb Wataghin, Dept Fis Aplicada, Campinas, SP - Brazil

^[2] Univ Sao Paulo, Inst Quim Sao Carlos, Dept Fisicoquim, Sao Carlos, SP - Brazil

• Tipo de documento: Artigo Científico
• Fonte: ChemPhysChem; v. 15, n. 17, p. 3864-3870, DEC 1 2014.
• Citações Web of Science: 1

Resumo

The ethanol oxidation reaction (EOR) is investigated on Pt/Au(hkl) electrodes. The Au(hkl) single crystals used belong to the {[}n(111)x(110)] family of planes. Pt is deposited following the galvanic exchange of a previously deposited Cu monolayer using a Pt2+ solution. Deposition is not epitaxial and the defects on the underlying Au(hkl) substrates are partially transferred to the Pt films. Moreover, an additional (100)-step-like defect is formed, probably as a result of the strain resulting from the Pt and Au lattice mismatch. Regarding the EOR, both vicinal Pt/Au(hkl) surfaces exhibit a behavior that differs from that expected for stepped Pt; for instance, the smaller the step density on the underlying Au substrate, the greater the ability to break the CC bond in the ethanol molecule, as determined by in situ Fourier transform infrared spectroscopy measurements. Also, we found that the acetic acid production is favored as the terrace width decreases, thus reflecting the inefficiency of the surface array to cleave the ethanol molecule. (AU)

• Processo FAPESP: 11/12566-3 - Caracterização eletrônica e estrutural de monocamadas de Pt depositadas em superfícies vicinais de Au
• Beneficiário: Mauricio Javier Prieto
• Modalidade de apoio: Bolsas no Brasil - Pós-Doutorado