Hostname: page-component-586b7cd67f-l7hp2 Total loading time: 0 Render date: 2024-11-24T16:50:19.629Z Has data issue: false hasContentIssue false
  • English
  • Français

Composition Dependence of Electrical Resistivity of Magnesium-cobalt Films During Hydridation and Dehydridation

Published online by Cambridge University Press:  01 February 2011

Yiu Bun Chan  and
Chung Wo Ong
Yiu Bun Chan
Affiliation:
[email protected], The Hong Kong Polytechnic University, Department of Applied Physics and Materials Research Center, Hung Hom, Kowloon, Hong Kong, N/A, China, People's Republic of
Chung Wo Ong
Affiliation:
[email protected], The Hong Kong Polytechnic University, Department of Applied Physics and Materials Research Center, Hung Hom, Kowloon, Hong Kong, N/A, China, People's Republic of
Get access

Abstract

Palladium (Pd)-coated magnesium-cobalt (Mg-Co) films were prepared by co-sputtering at various ratios of the sputtering power of Mg to that of Co (PMg/PCo). The elemental composition of the films varies coherently with PMg/PCo. Films of higher Mg contents are of stronger interest. Their structures are more disordered even when just a relatively small amount of Co is added. The respective elemental contents are not uniform along depth, but more Mg aggregate near the surface region. A substantial volume fraction of Mg oxide is present. Though of structural complications, a Mg-rich film shows stronger and faster resistivity (ρ) response when reacting with hydrogen. Soaking an as-deposited Mg-rich film in 15% H2 (in argon) gives a huge change of ρ by 40 times, but it is mainly due to some irreversible structural change when a freshly prepared sample is first brought into contact with H2. The change of ρ in subsequent hydridation-dehydridation cycles is about 50%, while the drift of the baseline is less severe. Co-rich films give much weaker resistivity response to H2.

Keywords

hydrogenationMgsputtering
Type
Research Article
Information
MRS Online Proceedings Library (OPL) , Volume 1042: Symposium S – Materials and Technology for Hydrogen Storage , 2007 , 1042-S02-05
Copyright
Copyright © Materials Research Society 2008

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

1. Huiberts, J.N., Griessen, R., Rector, J.H., Wijingaarden, R.J., Dekker, J.P., Groot, D.G. de and Koeman, N.J., Nature 380, 231 (1996).Google Scholar
2. Sluis, P. van der, Ouwerkerk, M. and Duine, P.A., Appl. Phys. Lett. 70, 3356 (1997).Google Scholar
3. Kersssemakers, J.W.J., Molen, S.J. van der, Koeman, N.J., Günther, R. and Griessen, R., Nature 406, 489 (2000).Google Scholar
4. Kersssemakers, J.W.J., Molen, S.J. van der, Günther, R., Dam, B. and Griessen, R., Phys. Rev. B 65, 075417 (2002).10.1103/PhysRevB.65.075417Google Scholar
5. Richardson, T.J., Slack, J.L., Armitage, R.D., Kostecki, R., Farangis, B. and Rubin, M.D., Appl. Phys. Lett. 78, 3047 (2001).Google Scholar
6. Yoshimura, K., Yamada, Y. and Okada, M., Appl. Phys. Lett. 81, 4709 (2002).10.1063/1.1530378Google Scholar
7. Farangis, B., Nachimuthu, P., Richardson, T.J., Slack, J.L., Meyer, B.K., Perera, R.C.C., Rubin, M.D., Solid State Ionics 165, 309 (2003).Google Scholar
8. Lohstroh, W., Westerwaal, R.J., Lokhorst, A.C., Mechelen, J.L.M. van, Dam, B., Griessen, R., J. Alloys Compd. 404–406, 490 (2005).Google Scholar
9. Richardson, T.J., Slack, J.L., Farangis, B., Rubin, M.D., Appl. Phys. Lett. 80, 1349 (2002).Google Scholar
10. Richardson, T.J., Farangis, B., Slack, J.L., Nachimuthu, P., Perera, R., Tamura, N., Rubin, M., J. Alloys Compd. 356–357, 204 (2003).Google Scholar
11. Gennari, F.C., Castro, F.J., J. Alloys Compd. 396, 182 (2005).Google Scholar