Hostname: page-component-cd9895bd7-8ctnn Total loading time: 0 Render date: 2024-12-27T02:22:21.178Z Has data issue: false hasContentIssue false
  • English
  • Français

Doping And Band-Gap Engineering Of An Intrazeolite Tungsten(Vi) Oxide Supralatiice

Published online by Cambridge University Press:  15 February 2011

Geoffrey A. Ozin ,
Andrzej Malek ,
Richard Prokopowicz ,
Peter M. Macdonald ,
Saim özkarb ,
Karin Mollerc  and
Thomas Bein.
Geoffrey A. Ozin
Affiliation:
Lash Miller Chemistry Laboratories, University of Toronto, 80 St. George Street, Toronto, Ontario, Canada M5S 1A1
Andrzej Malek
Affiliation:
Lash Miller Chemistry Laboratories, University of Toronto, 80 St. George Street, Toronto, Ontario, Canada M5S 1A1
Richard Prokopowicz
Affiliation:
Lash Miller Chemistry Laboratories, University of Toronto, 80 St. George Street, Toronto, Ontario, Canada M5S 1A1
Peter M. Macdonald
Affiliation:
Lash Miller Chemistry Laboratories, University of Toronto, 80 St. George Street, Toronto, Ontario, Canada M5S 1A1
Saim özkarb
Affiliation:
Chemistry Department, Middle East Technical University, Ankara, Turkey.
Karin Mollerc
Affiliation:
Department of Chemistry, University of New Mexico, Albuquerque, NM, 87131, USA
Thomas Bein.
Affiliation:
Department of Chemistry, University of New Mexico, Albuquerque, NM, 87131, USA
Get access

Abstract

New results are presented concerning the topotactic self-assembly, n-type doping and band-gap engineering of an intrazeolite tungsten(VI) oxide supralattice n(WO3)-Na56Y, where O < n ≤ 32, built-up of single size and shape (WO3)2 dimers. In particular it has been found that the oxygen content of these dimers can be quantitatively adjusted by means of a thermal vacuum induced reversible reductive-elimination oxidative-addition of dioxygen. This provides access to new n(WO3−x)−Na56Y materials (0 < x ≤ 1.0) in which the oxygen content, structural properties and electronic architecture of the dimers are changed. In this way one can precisely control the oxidation state, degree of n-doping and band-filling of a tungsten(VI) oxide supralattice through an approach which can be considered akin to, but distinct in detail to, that found in the Magneli crystallographic shear phases of non-stoichiometric bulk WO3−x. Another discovery concerns the ability to alter local electrostatic fields experienced by the tungsten(VI) oxide moieties housed in the 13Å supercages of 16(WO3)−M56Y, by varying the ionic potential of the constituent supercage M+ cations across the alkali metal series. This method provides the first opportunity to fine-tune the band-gap of a tungsten(VI) oxide supralattice. A miniband electronic description is advanced as a qualitative first attempt to understand the origin of the above effects. The implications of these discoveries are that cluster size, composition and intrinsic electrostatic field effects can be used to “chemically manipulate” (engineer) the doping and band architecture of intrazeolite supralattices of possible interest in quantum electronics and nonlinear optics.

Type
Research Article
Information
MRS Online Proceedings Library (OPL) , Volume 233: Symposium U – Synthesis/Characterization and Novel Applications of Molecular Sieve Materials , 1991 , 109
Copyright
Copyright © Materials Research Society 1991

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. Ozin, G.A. and Özkar, S., J. Phys. Chem., 94, 7556(1990).CrossRefGoogle Scholar
2. (a) Ozin, G.A., Özkar, S., Moller, K. and Bein, T., J. Amer. Chem. Soc., 112, 9575(1990); (b) G.A. Ozin, S. Ozkar and P.M. Macdonald, J. Phys. Chem., 94, 6939 (1990); (c) G.A. Ozin, S. Ozkar, K. Moller and T. Bein, J. Phys. Chem., (in press).Google Scholar
3. Varga, G.M., Papaconstantinou, E. and Pope, M.T., Inorg. Chem., 9, 662–667 (1970).Google Scholar
4. Ozin, G.A., Özkar, S., Malek, A., Macdonald, P.M., Pines, A., Jelinek, R., (work in progress).Google Scholar
5. Robota, H. (private communication).Google Scholar