Hostname: page-component-cd9895bd7-dzt6s Total loading time: 0 Render date: 2024-12-27T02:31:51.741Z Has data issue: false hasContentIssue false

Electrochemical Hydrogen Adsorption/Storage in Pure and Functionalized Single Wall Carbon Nanotubes

Published online by Cambridge University Press:  01 February 2011

Yubing Wang
Affiliation:
Department of Chemistry and Environmental Science, New Jersey Institute of Technology, Newark, New Jersey
Zafar Iqbal*
Affiliation:
Department of Chemistry and Environmental Science, New Jersey Institute of Technology, Newark, New Jersey
Get access

Abstract

Self-assembled sheets of single wall carbon nanotubes (SWNTs) were used as the working electrode for electrochemical hydrogen adsorption/storage in a three-electrode cell in 6M aqueous KOH or HNO3 solution. Hydrogen adsorption studies on pristine SWNTs, as well as SWNTs functionalized with electrodeposited nanoparticles of magnesium (Mg) and cobalt (Co), have been performed. The adsorbed hydrogen (uncorrected for possible water uptake via nanocapillarity) was measured to be 2.5 weight percent by thermogravimetric analysis (TGA) on a Mg-functionalized sample and 3.2 weight percent by Prompt-Gamma Activation Analysis (PGAA) for a pristine sample charged for 20 hrs. Weight loss occurs in the 105° to 125°C temperature range for both sample types. Hydrogen in Co-functionalized SWNTs and 6M HNO3 electrolyte appears to be strongly chemisorbed as indicated by the appearance of a C-H stretching line in the Fourier-transform infrared spectrum (FTIR) and absence of a desorption peak in the TGA data in the 25° to 600°C temperature range. Thermopower measurements scale with the TGA data and suggest that hydrogen uptake is associated with partial charge transfer. Ex-situ Raman spectroscopy shows a reproducible downshift of the SWNT tangential stretching mode consistent with charge transfer or chemisorption on electrochemical charging, and a substantial decrease under some conditions in resonance-enhanced intensity with increasing charging time. A SWNT sheet electrochemically coated with the conducting polymer polyaniline and then charged in 6M KOH shows possible hydrogen uptake of 1.5 weight % that desorbs at 70°C.

Type
Research Article
Copyright
Copyright © Materials Research Society 2005

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

REFERENCES

[1] Dillon, A.C., Jones, K.M., Bekkedahl, T.A., Kiang, C.H., Bethune, D.S., Heben, M.J., Nature (London) 386, 377 (1997).Google Scholar
[2] Nützenadel, C., Züttel, A., Chartouni, D., Schlapbach, L., Electrochemical and Solid-State Letters, 2, 30 (1999).Google Scholar
[3] Lee, S.M., Park, K.S., Choi, Y.C., Park, Y.S., Bok, J.M., Bae, D.J., Nahm, K.S., Choi, Y.G., Yu, S.C., Kim, N., Frauenheim, T., Lee, Y.H., Synthetic Metals, 113, 290 (2000).Google Scholar
[4] Ye, Y., Ahn, C.C., Witham, C., Fultz, B., Liu, J., Rinzler, A.G., Colbert, D., Smith, K.A., Smalley, R.E., Appl. Phys. Lett. 74, 2307 (1999).Google Scholar
[5] Chen, P., Wu, X., Lin, J., Tan, K.L., Science 285, 91 (1999).Google Scholar
[6] Dillon, A.C., Heben, M.J, Appl. Phys. A 72, 133 (2001).Google Scholar
[7] Hirscher, M., Becher, M., Haluska, M., Dettlaff-Weglikowska, U., Quintel, A., Duesberg, G.S., Choi, Y.-M., Downes, P., Hulman, M., Roth, S., Stepanek, I., Bernier, P., Appl. Phys. A 72, 129 (2001).Google Scholar
[8] Shiraishi, M., Takenobu, T., Ata, M., Chem. Phys. Lett. 367, 633 (2003).Google Scholar
[9] Kajiura, H., Tsutsui, S., Kadono, K., Kakuta, M., Ata, M., Murakami, Y., Appl. Phys. Lett., 82, 1105 (2003).Google Scholar
[10] Shiraishi, M., Takenobu, T., Yamada, A., Ata, M., Kataura, H., Chem. Phys. Lett. 358, 213 (2002).Google Scholar
[11] Ritschel, M., Uhlemann, M., Gutfleisch, O., Leonhardt, A., Graff, A., Täschner, Ch., Fink, J., Appl. Phys. Lett., 80, 2985 (2002).Google Scholar
[12] Wang, Y., Malhotra, S., Iqbal, Z., Mater. Res. Soc. Symp. Proc. 800, 351 (2004).Google Scholar