1. Electrochemical characteristics of La–Ni–Al thin films
- Author
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Li, Chi Ying Vanessa, Wang, Zhong Min, Liu, Shi, and Chan, Sammy Lap Ip
- Subjects
- *
ELECTROCHEMICAL analysis , *THIN films , *COPPER , *SPUTTERING (Physics) - Abstract
Abstract: AB5 based hydrogen storage thin films (LaNi4.25Al0.75), deposited on Cu substrate by dc magnetron sputtering, have been investigated in this paper. X-ray diffraction (XRD) revealed that the microstructure of the film was in crystal form. SEM, AFM and FIB analyses proved that on the surface there were many pores of approximately 15–40nm in diameter of random size. The cross section of the film revealed that it was rather dense and defect-free, with a uniform thickness of about 4.2μm. Electrochemical properties of the films were measured by simulated battery tests. The single layer LaNi4.25Al0.75 film undergoes a longer activation period than typical AB5 alloys in bulk and the maximum discharge capacity of the film was about 220mAh/g. Two electrochemical behaviour (distinct to the bulk materials) were observed for the film electrode in which there was an apparent increase in intermediate potential for each discharge process, as well as a local increase of discharge potential during its activation period. [Copyright &y& Elsevier]
- Published
- 2008
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