Effect of sodium borohydride on the hydrogen diffusion in MmNi(3.6)Mn(0.4)Al(0.3)Co(0.7) hydride electrode

• Type: Article in International Conference Proceedings Book
• Date: 2008

Authors

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

Conference proceedings International

Title: DIFFUSION IN SOLIDS AND LIQUIDS III

Pages: 590-593

3rd International Conference on Diffusion in Solids and Liquids

Algarve, PORTUGAL, JUL 04-06, 2007

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ISI Web of Knowledge - 3 Citations

Scopus - 4 Citations

Other information

Authenticus ID: P-004-31B

Abstract (EN): Anodic polarisation curves of treated and untreated MmNi(3.6)Mn(0.4)Al(0.3)CO(0.7) (Mm = mischmetal) electrodes were measured under the conditions of various initial concentrations of absorbed hydrogen (HIM), rates of potential sweep and temperatures. The alloy powders of the electrodes were treated with 6 M NaOH solution containing y M NaBH4 (y = 0.0, 0.005, 0.01, 0.02, 0.03 and 0.05). The initial concentration of absorbed hydrogen in the electrodes varied between 0 and 0.06 HIM, and the working temperature range was 15 degrees C to 50 degrees C. Anodic peak current (I-p) at the MmNi(3.6)Mn(0.4)Al(0.3)Co(0.7) electrodes increased with an increase in the y value. In addition, the I-p value depended linearly on initial hydrogen concentration and square root of potential rate irrespective of y value. Furthermore, the activation energy for hydrogen diffusion decreased with an increase in y value. From these results, it is considered that the hydrogen diffusion in the MmNi(3.6)Mn(0.4)Al(0.3)Co(0.7) alloys and the electrocatalytic activity at their surfaces influence the I-p value and that they are important factors for improving the charge-discharge performance of the negative hydride electrode. Its low temperature (15-30 degrees C) performances are also improved by the simple powder treatment with the 6 M NaOH solution containing NaBH4 as reducing agent.

Language: English

Type (Professor's evaluation): Scientific

No. of pages: 4