Anodic polarisation characterisation of absorbed hydrogen in modified Mm(B5)x alloys

• Type: Article in International Scientific Journal
• Date: 2008

Authors

Chen, Y (Author) Other; Sequeira, CAC (Author) Other

Journal

Title: Defect and Diffusion Forum

Vol. 283-286

Pages: 622-627

ISSN: 1012-0386

Publisher: Trans Tech Publications Ltd

Indexing

Scopus - 2 Citations

Other information

Authenticus ID: P-007-PRS

DOI: 10.4028/3-908454-50-6.622

Abstract (EN): Anodic polarisation curves of Mm(Ni3.6Co0.7Mn 0.4Al0.3)x (Mm = mischmetal, 0.85 < x < 1.15) electrodes were measured under the conditions of various initial concentrations of absorbed hydrogen (H/M), potential sweeping rates (v), temperatures (T), and amounts of reducing agent (y = [NaBH4) in alkaline solution. Anodic peak current (Ip) at the Mm(B 5)x electrodes increased with an increase in T, x and y values. In addition, the Ip value depended linearly on initial hydrogen concentration and square root of potential sweeping rate, irrespective of T, x and y values. Furthermore, the activation energy for hydrogen diffusion decreased with an increase in x and y values. From these results, it is considered that the surface reduction treatment of the Mm(B5) x alloys, performed in alkaline solution with sodium borohydride, the nonstoichiometry and the initial concentration of absorbed hydrogen, are important factors for improving the charge-discharge performance of negative electrodes for metal-hydrogen energy systems.

Language: English

Type (Professor's evaluation): Scientific