Pd/Ni Synergestic Activity for Hydrogen Oxidation Reaction in Alkaline Conditions

详细信息    查看全文

• 作者：Istvá ; n Bakos^a ; Andrá ; s Paszterná ; k^a ; David Zitoun^b ; ^{David.Zitoun@biu.ac.il" class="auth_mail" title="E-mail the corresponding author}
• 刊名：Electrochimica Acta
• 出版年：2015
• 出版时间：10 September 2015
• 年：2015
• 卷：176
• 期：Complete
• 页码：1074-1082
• 全文大小：1869 K

文摘

The investigation of hydrogen oxidation reaction (HOR) in alkaline conditions has been the subject of a wide interest in the past few years with the rise of alkaline membrane fuel cells (AMFCs). In particular, the quest for the lowest content of platinum group metals (PGMs) in the HOR catalyst is ongoing. In this article, we propose the use of a nanoscale Pd layer partially covering a Ni film to provide the most efficient use of the PGM in the HOR catalyst. The Pd/Ni electrodes were prepared by spontaneous and electrolytic deposition of Pd onto smooth polycrystalline Ni surfaces with different surface compositions. The electrodes were characterized by cyclic voltammetry and atomic force microscopy. Electrocatalytic activity in HOR of the Pd/Ni electrodes was measured in alkaline solution by rotating disc electrode method. In the manuscript, we demonstrate that a Pd coverage as low as 1.5% vs. Ni coverage is sufficient to provide a high current density compared to pure Ni. The current density linearly increases with the Pd coverage up to a Pd coverage of 17%; upon further increase in the Pd coverage, the current density reaches a plateau, i.e. the diffusion limit for the HOR process. The comparison with Pd supported on carbon shows the clear benefit for the bimetallic catalyst.