Extended X-ray Absorption Fine Structure and X-ray Diffraction Examination of Sputtered Nickel Carbon Binary Thin Films for Fuel Cell Applications

详细信息    查看全文

• 作者：Bridget Ingham ; Nicola Gaston ; Kieran Fahy ; Xiao Yao Chin ; Christian J. Dotzler ; Eric Rees ; Gareth Haslam ; Zoe H. Barber ; G. Timothy Burstein ; Mary P. Ryan
• 刊名：The Journal of Physical Chemistry C
• 出版年：2012
• 出版时间：March 15, 2012
• 年：2012
• 卷：116
• 期：10
• 页码：6159-6165
• 全文大小：317K
• 年卷期：v.116,no.10(March 15, 2012)
• ISSN：1932-7455

文摘

Extended X-ray absorption fine structure (EXAFS) and X-ray diffraction (XRD) are used to study the structure of sputtered binary nickel carbon alloy films (5鈥?4 atom % Ni) for use as potential electrocatalysts in acidic solutions. Three compositional regions are identified: 鈥渓ow鈥?(5 atom % Ni), where the structure consists mainly of isolated Ni atoms or dimers in a carbon matrix; 鈥渕edium鈥?(11鈥?4 atom % Ni), where the Ni鈥揘i nearest-neighbor coordination is increased but there is little longer-range order; and 鈥渉igh鈥?(35鈥?4 atom % Ni), where crystalline Ni₃C is formed. This indicates a threshold concentration of Ni of between 25 and 35 at% before Ni₃C starts to form.