Skip to main content

Thank you for visiting nature.com. You are using a browser version with limited support for CSS. To obtain the best experience, we recommend you use a more up to date browser (or turn off compatibility mode in Internet Explorer). In the meantime, to ensure continued support, we are displaying the site without styles and JavaScript.

Mesostructured germanium with cubic pore symmetry

Abstract

Regular mesoporous oxide materials have been widely studied1,2,3,4,5,6,7,8 and have a range of potential applications, such as catalysis, absorption and separation. They are not generally considered for their optical and electronic properties. Elemental semiconductors with nanopores running through them represent a different form of framework material with physical characteristics contrasting with those of the more conventional bulk, thin film and nanocrystalline forms1. Here we describe cubic mesostructured germanium, MSU-Ge-1, with gyroidal channels containing surfactant molecules, separated by amorphous walls that lie on the gyroid (G) minimal surface as in the mesoporous silica MCM-48 (ref. 2). Although Ge is a high-melting, covalent semiconductor that is difficult to prepare from solution polymerization, we succeeded in assembling a continuous Ge network using a suitable precursor for Ge4- atoms. Our results indicate that elemental semiconductors from group 14 of the periodic table can be made to adopt mesostructured forms such as MSU-Ge-1, which features two three-dimensional labyrinthine tunnels obeying space group symmetry and separated by a continuous germanium minimal surface that is otherwise amorphous. A consequence of this new structure for germanium, which has walls only one nanometre thick, is a wider electronic energy bandgap (1.4 eV versus 0.66 eV) than has crystalline or amorphous Ge. Controlled oxidation of MSU-Ge-1 creates a range of germanium suboxides with continuously varying Ge:O ratio and a smoothly increasing energy gap.

Your institute does not have access to this article

Relevant articles

Open Access articles citing this article.

Access options

Buy article

Get time limited or full article access on ReadCube.

$32.00

All prices are NET prices.

Figure 1: 1 X-ray scattering of mesostructured MSU-Ge-1, bicontinuous gyroid minimal surface and energy-dispersive X-ray spectrum.
Figure 2: TEM images of mesoporous germanium semiconductor MSU-Ge-1.
Figure 3: PDF analysis, FTIR and optical absorption spectra and TGA data.

References

  1. Ozin, G. A. Nanomaterials—endosemiconductors and exosemiconductors. Mater. Chem. Adv. Chem. Ser. 245, 335–371 (1995)

    CAS  Google Scholar 

  2. Kresge, C. T., Leonowicz, M. E., Roth, W. J., Vartuli, J. C. & Beck, J. S. Ordered mesoporous molecular sieves synthesized by a liquid-crystal template mechanism. Nature 359, 710–712 (1992)

    ADS  CAS  Article  Google Scholar 

  3. Asefa, T. et al. Periodic mesoporous organosilicas with organic groups inside the channel walls. Nature 402, 867–871 (1999)

    ADS  CAS  Article  Google Scholar 

  4. Inagaki, S., Guan, S., Ohsuna, T. & Terasaki, O. An ordered mesoporous organosilica hybrid material with a crystal-like wall structure. Nature 416, 304–307 (2002)

    ADS  CAS  Article  PubMed  Google Scholar 

  5. Tian, Z.-R. et al. Manganese oxide mesoporous structures: mixed-valent semiconducting catalysts. Science 276, 926–930 (1997)

    CAS  Article  Google Scholar 

  6. Antonelli, D. M. & Ying, J. Y. Synthesis of a stable hexagonally packed mesoporous niobium oxide molecular sieve through a novel ligand-assisted templating mechanism. Angew. Chem. Int. Edn Engl. 35, 426–430 (1996)

    CAS  Article  Google Scholar 

  7. Lu, Q., Gao, F., Li, Y., Zhou, Y. & Zhao, D. Synthesis of germanium oxide mesoporous with a new intermediate state. Micropor. Mesopor. Mater. 56, 219–225 (2002)

    CAS  Article  Google Scholar 

  8. Zou, X., Conradsson, T., Klingstedt, M., Dadachov, M. S. & O'Keeffe, M. A mesoporous germanium oxide with crystalline pore walls and its chiral derivative. Nature 437, 716–719 (2005)

    ADS  CAS  Article  PubMed  Google Scholar 

  9. MacLachlan, M. J., Coombs, N. & Ozin, G. A. Non-aqueous supramolecular assembly of mesostructured metal germanium sulphides from (Ge4S10)4- clusters. Nature 397, 681–684 (1999)

    ADS  CAS  Article  Google Scholar 

  10. Trikalitis, P. N., Rangan, K. K., Bakas, T. & Kanatzidis, M. G. Varied pore organization in mesostructured semiconductors based on the [SnSe4]4- anion. Nature 410, 671–675 (2001)

    ADS  CAS  Article  PubMed  Google Scholar 

  11. Rangan, K. K., Trikalitis, P. N. & Kanatzidis, M. G. Light-emitting meso-structured sulfides with hexagonal symmetry: supramolecular assembly of [Ge4S10]4- clusters with trivalent metal ions and cetylpyridinium surfactant. J. Am. Chem. Soc. 122, 10230–10231 (2000)

    CAS  Article  Google Scholar 

  12. Attard, G. S. et al. Mesoporous platinum films from lyotropic liquid crystalline phases. Science 278, 838–840 (1997)

    ADS  CAS  Article  Google Scholar 

  13. Attard, G. S. et al. Liquid-crystal templates for nanostructured metals. Angew. Chem. Int. Edn Engl. 36, 1315–1317 (1997)

    CAS  Article  Google Scholar 

  14. Mohanan, J. L., Arachchige, I. U. & Brock, S. L. Porous semiconductor chalcogenide aerogels. Science 307, 397–400 (2005)

    ADS  CAS  PubMed  Google Scholar 

  15. Dunlap, W. C. Intrinsic conductivity of germanium. Science 112, 419–420 (1950)

    Article  Google Scholar 

  16. Bundy, F. P. & Kasper, J. S. A new dense form of solid germanium. Science 139, 340–342 (1963)

    ADS  CAS  Article  PubMed  Google Scholar 

  17. Tauc, J., Grigorov, R. & Vancu, A. Optical properties and electronic structure of amorphous germanium. Phys. Status Solidi (b) 15, 627–637 (1966)

    ADS  CAS  Article  Google Scholar 

  18. Gerion, D. et al. Solution synthesis of germanium nanocrystals: success and open challenges. Nano Lett. 4, 597–602 (2004)

    ADS  CAS  Article  Google Scholar 

  19. Taylor, B. R., Kauzlarich, S. M., Lee, H. W. H. & Delgado, G. R. Solution synthesis and characterization of quantum confined Ge nanoparticles. Chem. Mater. 11, 2493–2500 (1999)

    CAS  Article  Google Scholar 

  20. Das, A. K., Kamila, J. & Dev, B. N. Self-assembled Ge nanostructures on polymer-coated silicon: Growth and characterization. Appl. Phys. Lett. 77, 951–953 (2000)

    ADS  CAS  Article  Google Scholar 

  21. Zhu, Y., Yuan, C. L. & Ong, P. P. Enhancement of photoluminescence in Ge nanoparticles by neighboring amorphous C in composite Ge/C thin films. J. Appl. Phys. 93, 6029–6033 (2003)

    ADS  CAS  Article  Google Scholar 

  22. Alfredsson, V. & Anderson, M. W. Structure of MCM-48 revealed by transmission electron microscopy. Chem. Mater. 8, 1141–1146 (1996)

    CAS  Article  Google Scholar 

  23. Billinge, S. J. L. & Kanatzidis, M. G. Beyond crystallography: the study of disorder, nanocrystallinity and crystallographically challenged materials with pair distribution functions. Chem. Commun. 7, 749–760 (2004)

    Article  Google Scholar 

  24. Temkin, R. J., Paul, W. & Connell, G. A. N. Amorphous germanium. Structural properties. Adv. Phys. 22, 581–641 (1973)

    ADS  CAS  Article  Google Scholar 

  25. Price, D. L. & Saboungi, M.-L. Structure of vitreous germania. Phys. Rev. Lett. 81, 3207–3210 (1998)

    ADS  CAS  Article  Google Scholar 

  26. Nakamura, Y., Watanabe, K., Fukuzawa, Y. & Ichikawa, M. Observation of the quantum-confinement effect in individual Ge nanocrystals on oxidized Si substrates using scanning tunneling spectroscopy. Appl. Phys. Lett. 87, 133119 (2005)

    ADS  Article  Google Scholar 

  27. Davis, M. E. Ordered porous materials for emerging applications. Nature 417, 813–821 (2002)

    ADS  CAS  Article  PubMed  Google Scholar 

  28. Klemm, W. & Westlinning, Z. Untersuchungen über die Verbindungen des Magnesiums mit den Elementen der IV b-Gruppe. Z. Anorg. Allg. Chem. 245, 365–380 (1941)

    CAS  Article  Google Scholar 

  29. Broxon, T. J. & Chung, R. P.-T. Micellar bound meisenheimer complexes. J. Org. Chem. 55, 3886–3890 (1990)

    Article  Google Scholar 

Download references

Acknowledgements

We thank C. Malliakas for his help with the PDF data processing. We thank the National Science Foundation for financial support.

Author information

Authors and Affiliations

Authors

Corresponding author

Correspondence to Mercouri G. Kanatzidis.

Ethics declarations

Competing interests

Reprints and permissions information is available at npg.nature.com/reprintsandpermissions. The authors declare no competing financial interests.

Supplementary information

Supplementary Notes

This file contains Supplementary Figures and Legends 1–2 and Supplementary Discussions about the chemical environment of Ge atoms of MSU-Ge-1 semiconductor by X-ray photoelectron spectroscopy (XPS) experiments; including Supplementary Figure 3. (DOC 1077 kb)

Rights and permissions

Reprints and Permissions

About this article

Cite this article

Armatas, G., Kanatzidis, M. Mesostructured germanium with cubic pore symmetry. Nature 441, 1122–1125 (2006). https://doi.org/10.1038/nature04833

Download citation

  • Received:

  • Accepted:

  • Issue Date:

  • DOI: https://doi.org/10.1038/nature04833

Further reading

Comments

By submitting a comment you agree to abide by our Terms and Community Guidelines. If you find something abusive or that does not comply with our terms or guidelines please flag it as inappropriate.

Search

Quick links

Nature Briefing

Sign up for the Nature Briefing newsletter — what matters in science, free to your inbox daily.

Get the most important science stories of the day, free in your inbox. Sign up for Nature Briefing