Hostname: page-component-586b7cd67f-l7hp2 Total loading time: 0 Render date: 2024-11-25T18:03:16.596Z Has data issue: false hasContentIssue false
  • English
  • Français

A New Family of Light Emitting Si Nanoparticles

Published online by Cambridge University Press:  28 May 2012

Naoto Shirahata
Naoto Shirahata*
Affiliation:
Nanoarchitectonics Research Center (WPI-MANA), National Institute for Materials Science (NIMS), 1-2-1 Sengen, Tsukuba, 305-0047, Japan
Get access

Abstract

Color-tuning of UV luminescent silicon nanocrystals (Si NCs) was successfully achieved by precise size control of non-oxidized NCs. The alkoxy-capped Si NCs was synthesized via sodium biphenylide reduction of SiCl4 encapsulated with inverse micelles, and subsequent alkoxylation of surface Si-Cl bonds. Due to the high molecular packing density of alkoxy monolayers, outermost surface of the NCs was completely protected from oxidation even under ambient conditions. Interestingly, the optical absorption and emission spectra were blueshifted with reduction of non-oxidized NC size, and we found strong light emission in the UV range when the NCs were smaller than 2.5 nm. More than 20% of PL quantum efficiencies (QYs) were estimated from those UV luminescent NCs. Monodispersed NCs without oxide can provided narrow PL spectra with 35-40 nm of line-widths, while the presence of oxidized surface region of NCs led to the broad PL spectra. In addition, the redshift of PL spectra were observed from the partially-oxidized NCs which were formed due to the lower surface molecular coverage, suggesting the significant difference in optical transition of photogenerated carriers between the non-oxidized and the partially-oxidized NCs. This can be well-illustrated by comparing decay profiles of the carriers for each sample through the time-resolved PL spectroscopic observation.

Type
Research Article
Information
MRS Online Proceedings Library (OPL) , Volume 1437: Symposium L – Group IV Photonics for Sensing and Imaging , 2012 , mrss12-1437-l05-04
Copyright
Copyright © Materials Research Society 2012

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.a) Shirahata, N., Phys. Chem. Chem. Phys. 13, 7284 (2011).; b) E. F. Schubert and J. K. Kim, Science 308, 1274(2005).; c) V. Sukhovatkin, S. Hinds, L. Brzozowski and E. H. Sargent, Science 324, 542 (2009).Google Scholar
2. Canham, L. T., Appl. Phys. Lett. 57, 1046 (1990).Google Scholar
3. Shirahata, N., Hirakawa, D. and Sakka, Y., Green Chem. 12, 2139 (2010).Google Scholar
4. Shirahata, N., Tsuruoka, T., Hasegawa, T. and Sakka, Y., Small 6, 915 (2010).Google Scholar
5. Shirahata, N., Linford, M. R., Furumi, S., Pei, L., Sakka, Y., Gates, R. J. and Asplund, M. C., Chem. Commun. 4684 (2009).Google Scholar
6.a) Xia, H., He, Y. L., Wang, L. C., Zhang, W., Liu, X. N., Zhang, X. K., Feng, D. and Jackson, H. E., Appl. Phys. Lett. 78, 6705 (1995).; b) M. Ehbrecht, B. Kohn, F. Huisken, M. A. Laguna and V. Paillard, Phys. Rev. B 56, 6958(1997).; c) P. Shen, N. Uesawa, S. Inasawa, Y. Yamaguchi, J. Mater. Chem. 20, 1669 (2010).; d) S. –K. Ma and J. T. Lue, Thin Solid Films 304, 353 (1997).; e) J. von Behren, T. van Buuren, M. Zacharias, E.H. Chimowitz and P.M. Fauchet, Solid State Commun. 105, 317 (1998).; f) Shikuan Yang, Weiping Cai, Haibo Zeng, and Zhigang Li, J. Appl. Phys. 104, 23516 (2008).Google Scholar
7. Shirahata, N., Hozumi, A. and Yonezawa, T., Chem. Rec. 5, 145 (2005).Google Scholar
8. Godefroo, S., Hayne, M., Jivanescu, M., Stesmans, A., Zacharias, M., Lebedev, O. I., van Tendeloo, G. and Moshchalkov, V. V. Nat. Nanotechnol. 3, 174 (2008).Google Scholar
9. Shirahata, N. and Sakka, Y., J. Ceram. Soc. Jpn. 118, 932 (2010).Google Scholar