Platinum-rare earth electrodes for hydrogen evolution in alkaline water electrolysis

• Tipo: Artigo em Revista Científica Internacional
• Data: 2013

Autores

D.M.F. Santos (Autor) Outra; C.A.C. Sequeira (Autor) Outra; D. Macciò (Autor) Outra; A. Saccone (Autor) Outra; José Luís Figueiredo (Autor) FEUP

Revista

Título: International Journal of Hydrogen Energy

Vol. 38

Páginas: 3137-3145

ISSN: 0360-3199

Editora: Elsevier

Indexação

ISI Web of Knowledge - 18 Citações

ISI Web of Science

Scopus - 15 Citações

Classificação Científica

FOS: Ciências da engenharia e tecnologias

Outras Informações

ID Authenticus: P-005-2FK

DOI: 10.1016/j.ijhydene.2012.12.102

Abstract (EN): In the new "Hydrogen Economy" concept, water electrolysis is considered one of the most promising technologies for hydrogen production. Novel electrocatalytic materials for the hydrogen electrode are being actively investigated to improve the energy efficiency of current electrolysers. Platinum (Pt) alloys are known to possess good catalytic activities towards the hydrogen evolution reaction (HER). However, virtually nothing is known about the effects of rare earth (RE) elements on the electrocatalytic behaviour of Pt towards the HER. In this study, the hydrogen discharge is evaluated in three different Pt RE intermetallic alloy electrodes, namely Pt-Ce, Pt-Sm and Pt Ho, all having equiatomic composition. The electrodes are tested in 8 M KOH aqueous electrolytes at temperatures ranging from 25 degrees C to 85 degrees C. Measurements of the HER by linear scan voltammetry allow the determination of several kinetic parameters, namely the Tafel coefficients, charge-transfer coefficients, and exchange current densities. Activation energies of 46, 59, 39, and 60 kJ mol(-1) are calculated for Pt, Pt-Ce, Pt-Sm and Pt-Ho electrodes, respectively. Results show that the addition of REs improves the activity of the Pt electrocatalyst. Studies are in progress to correlate the microstructure of the studied alloys with their performance towards the HER. Copyright

Idioma: Inglês

Tipo (Avaliação Docente): Científica

Nº de páginas: 9