Ethanol electrooxidation on PdIr/C electrocatalysts in alkaline media: electrochemical and fuel cell studies

Author(s)

Neto, A. O. ^[1] ; da Silva, S. G. ^[1] ; Buzzo, G. S. ^[1] ; de Souza, R. F. B. ^[1] ; Assumpcao, M. H. M. T. ^[1] ; Spinace, E. V. ^[1] ; Silva, J. C. M. ^[1]

Affiliation

^[1] IPEN, CNEN, SP, BR-05508900 Sao Paulo - Brazil

• Document type: Journal article
• Source: IONICS; v. 21, n. 2, p. 487-495, FEB 2015.
• Web of Science Citations: 14

Abstract

PdIr/C electrocatalysts in different atomic ratios (Pd:Ir 90:10, 70:30, and 50:50), Pd/C and Ir/C supported on Vulcan XC 72 carbon were tested for ethanol electrooxidation in alkaline media. The electrocatalysts were prepared by borohydride reduction method. The electrocatalysts were characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM), energy dispersive spectroscopy (EDS), cyclic voltammetry (CV), and chronoamperometry (CA). The XRD measurements suggested the PdIr alloy formation. EDS analyses showed the real atomic ratios similar to the nominal ones. TEM showed the average particle diameter between 4.6 and 5.8 nm for all compositions prepared. The catalytic activity for ethanol electrooxidation in alkaline medium investigated by CV and CA at room temperature showed that PdIr/C (90:10) exhibited higher performance for ethanol oxidation in comparison with others PdIr/C compositions, Pd/C and Ir/C, while the experiments on a single direct ethanol alkaline fuel cell at 70 A degrees C showed higher performance for PtIr (70:30). The best results obtained using PdIr/C electrocatalysts may be associated to the electronic effect between Pd and Ir that might cause a decrease of poisoning on catalyst and the occurrence of bifunctional mechanism. (AU)

• FAPESP's process: 12/22731-4 - Electrocatalysts SUPPORTED IN DIFFERENT SUBSTRATES prepared by codeposition electrochemistry for direct liquid fuel cell (methanol , ethanol and formic acidic)
• Grantee: Guilherme Soares Buzzo
• Support Opportunities: Scholarships in Brazil - Post-Doctoral
• FAPESP's process: 11/18246-0 - Preparation of PD binary and ternary electrocatalysts by borohydride reduction for alcohol electro-oxidation in alkaline medium
• Grantee: Almir Oliveira Neto
• Support Opportunities: Regular Research Grants
• FAPESP's process: 13/01577-0 - Development of materials and degradation studies of electrocatalysts and supports for alkaline fuel cell
• Grantee: Júlio César Martins da Silva
• Support Opportunities: Scholarships in Brazil - Post-Doctoral
• FAPESP's process: 12/03516-5 - Oxides-C supported electrocatalysts for direct liquid fuel cell anodes
• Grantee: Rodrigo Fernando Brambilla de Souza
• Support Opportunities: Scholarships in Brazil - Post-Doctoral