Hostname: page-component-586b7cd67f-t7czq Total loading time: 0 Render date: 2024-12-01T09:12:25.275Z Has data issue: false hasContentIssue false

Laser-assisted chemical vapor deposition of carbon coated cobalt nanoparticles

Published online by Cambridge University Press:  26 February 2011

Oscar Alm
Affiliation:
[email protected], Dept. of Materials Chemistry, Uppsala University, Box 538, SE-751 21 Uppsala, Uppsala, N/A, N/A, Sweden, +46 18 471 3737
J.-O. Carlsson
Affiliation:
Department of Materials Chemistry, The Ångström Laboratory, Uppsala University, P. O. Box 538, SE-751 21 Uppsala, Sweden
M. Boman
Affiliation:
Department of Materials Chemistry, The Ångström Laboratory, Uppsala University, P. O. Box 538, SE-751 21 Uppsala, Sweden
Get access

Abstract

Carbon coated nanoparticles were synthesized by laser-assisted (ArF excimer laser, λ = 193 nm) chemical vapor deposition (LCVD). The particles were formed in the gas-phase by photolytic dissociation of cobaltocene in argon and the particles were deposited onto a silicon substrate. The particles were deposited at two different laser fluencies, 70 and 300 mJ/cm2.

Single crystalline spherical cobalt particles with a well-defined carbon shell were observed by transmission electron microscopy (TEM) for the highest fluence, 300 mJ/cm2. The metallic nucleus phase were identified as either β-Co or Co3O4. Polycrystalline particles were deposited at 70 mJ/cm2, these particles contained α-Co, β-Co, CoO and Co3O4. The particles deposited at 300 mJ/cm2 were log-normally distributed and the total diameter had a mean geometric size of 25 nm while the nuclei had a mean diameter of 10 nm. X-ray photoelectron spectroscopy (XPS) measurements showed that the particles had a carbon content roughly ten times the amount of cobalt. Sputtering showed that both cobalt oxide and metallic cobalt was present. HRTEM micrographs of the particles revealed that only one phase was present in the whole nucleus, proving the nuclei were either oxide or metallic. Raman spectroscopy showed that that the carbon shell contained mostly amorphous carbon. Small domains of carbon of more graphitic character was embedded in the amorphous carbon shell in the 300 mJ/cm2 sample.

Type
Research Article
Copyright
Copyright © Materials Research Society 2006

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 Cao, G., Nanostructures and nanomaterials, synthesis, properties and applications, Imperial college press, (2004).Google Scholar
2 Gubin, S. P., Koksharov, Yu. A., Inorg. Mater. 38 10851099 (2002).Google Scholar
3 Elihn, K., Otten, F., Boman, M., Heszler, P., Kruis, F. E., Fissan, H., Carlsson, J.O., Appl. Phys. A 72, 2934 (2001).Google Scholar
4 Heszler, P., Ehlin, K., Boman, M., Carlsson, J.O.. Appl. Phys. A 70, 613616 (2000).Google Scholar
5 Ehlin, K., Landström, L., Heszler, P., Appl. Surf. Sci. 186 573577 (2002).Google Scholar
6 Heszler, P., Ehlin, K., Landström, L., Boman, M., Smart Mater. Struct. 11(5) 631639 (2002).Google Scholar
7 Landström, L., Ehlin, K., Boman, M., Granqvist, C. G., Heszler, P., Appl. Phys. A. 81(4), 827833 (2005).Google Scholar
8 Kalska, B., Paggel, J. J., Fumagalli, P., Hilgendorff, M., Giersig, M., J. Appl. Phys, 92 (21), 74817485 (2002).Google Scholar
9 Dong, X. L., Choi, C. J., Kim, B. K., Scripta Mater. 47 857861 (2002).Google Scholar
10 Kitakami, O., Sato, H., Shimada, Y., Sato, F., Tanaka, M., Phys. Rev. B: Condens. Matter. 56 (21) 1384913854 (1997).Google Scholar
11 Hayashi, H., Ohno, T., Yatsuya, S., Uyeda, R., Jpn. J. Appl. Phys. 16(5) 705717 (1977).Google Scholar
12 Cattaruzza, E., Battaglin, G., Canton, P., Fernàndez, C. de Julián, Ferroni, M., Finotto, T., Maurizio, C., Sada, C., J. Non-Cryst. Solids. 336 148152 (2004).Google Scholar
13 Petit, C., Wang, Z. L., Pileni, M. P., J. Phys. Chem B. 109 1530915316 (2005).Google Scholar
14 Bonard, J.M., Seraphin, S., Wegrowe, J.E., Jiao, J., Chätelain, A., Chem. Phys. Lett. 343 251257 (2001).Google Scholar
15 Jiao, J., Seraphin, S., J. Appl. Phys. 83 (5) 24422448 (1998).Google Scholar
16 Sun, X.C., Reyes-Gagsa, J., Dong, X. L.. Mol. Phys. 100 (19) 31473150 (2002).Google Scholar
17 Flahaut, E., Agnoli, F., Sloan, J., O'Connor, C., Green, M. L. H., Chem. Mater. 14 25532558 (2002).Google Scholar
18 Nishide, D., Kataura, H, Suzuki, S., Okubo, S., Achiba, Y., Chem. Phys. Lett. 392 309313 (2004).Google Scholar
19 Schulmeister, K., Lunney, J. G., Buckley, B., J. Appl.Phys, 72 (8) 34803484 (1992)Google Scholar
20 Kim, Y.G., Byun, D., Hutchings, C., Dowben, P. A., J. Appl.Phys, 70 (10) 60626064 (1992)Google Scholar
21 Hwang, S.D., Kim, Y.G., Wu, C., Dowben, P. A., Mater. Sci. Eng., B 20 L1–L4 (1993)Google Scholar
22 Oku, M., Sato, Y., Appl. Surf. Sci. 55 3741 (1992).Google Scholar
23 Jiménez, V.M, Fernández, A., Espinós, J.P., González-Elipe, A.R., J. Electron. Spectrosc. Relat. Phenom., 71 6171 (1995)Google Scholar
24 Landstrom, L., Kokavecz, J., Lu, J., Heszler, P.; J. Appl.Phys, 95 (8) 44084414 (2004)Google Scholar