Stabilization of intrazeolitic cadmium telluride nanoclusters by ion exchange

Elaine S. Brigham, Carl S. Weisbecker, Walter E. Rudzinski, Thomas E. Mallouk

Research output: Contribution to journalArticle

39 Citations (Scopus)

Abstract

Cadmium telluride nanoclusters were prepared by vapor-phase deposition of elemental tellurium in Na+-zeolite A, followed by partial exchange of the zeolite with aqueous Cd-(NO3)2, and reduction with hydrogen at 450 °C. The stability of the nanoclusters in environments that normally cause rapid Ostwald ripening or oxidation (air, water, and Br2/ MeOH) was greatly enhanced by exchanging the Na+-zeolite with K+ after the Te° deposition and hydrogen reduction steps. Exchange of K+ for Na+ narrows the effective pore diameter of zeolite A from 4.0 to 3.3 Å, inhibiting the diffusion of larger atoms, ions, and molecules (Te°, Te2-, and Br2). Distinct absorption maxima in diffuse reflectance UV-visible spectra and sharp exciton peaks in low-temperature excitation spectra verified the presence of quantum-confined CdTe. These spectral features are largely unchanged when the material, in its K+-exchanged form, is exposed to air and water for periods of months. Under the same conditions, materials in the Na+ form are rapidly degraded. TEM micrographs of the K+-exchanged materials show 20-50 Å diameter nanoclusters dotted throughout the zeolite matrix. The partial loss of host crystallinity observed in X-ray diffraction patterns suggests that the process of cluster formation involves aggregation within the large cages of the zeolite and local destruction of the pore network.

Original languageEnglish (US)
Pages (from-to)2121-2127
Number of pages7
JournalChemistry of Materials
Volume8
Issue number8
DOIs
StatePublished - Jan 1 1996

Fingerprint

Zeolites
Cadmium telluride
Nanoclusters
Ion exchange
Stabilization
Ostwald ripening
Hydrogen
Tellurium
Air
Excitons
Diffraction patterns
Water
Agglomeration
Vapors
Transmission electron microscopy
X ray diffraction
Atoms
Oxidation
Molecules
Ions

All Science Journal Classification (ASJC) codes

  • Chemistry(all)
  • Chemical Engineering(all)
  • Materials Chemistry

Cite this

Brigham, E. S., Weisbecker, C. S., Rudzinski, W. E., & Mallouk, T. E. (1996). Stabilization of intrazeolitic cadmium telluride nanoclusters by ion exchange. Chemistry of Materials, 8(8), 2121-2127. https://doi.org/10.1021/cm960045s
Brigham, Elaine S. ; Weisbecker, Carl S. ; Rudzinski, Walter E. ; Mallouk, Thomas E. / Stabilization of intrazeolitic cadmium telluride nanoclusters by ion exchange. In: Chemistry of Materials. 1996 ; Vol. 8, No. 8. pp. 2121-2127.
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Brigham, ES, Weisbecker, CS, Rudzinski, WE & Mallouk, TE 1996, 'Stabilization of intrazeolitic cadmium telluride nanoclusters by ion exchange', Chemistry of Materials, vol. 8, no. 8, pp. 2121-2127. https://doi.org/10.1021/cm960045s

Stabilization of intrazeolitic cadmium telluride nanoclusters by ion exchange. / Brigham, Elaine S.; Weisbecker, Carl S.; Rudzinski, Walter E.; Mallouk, Thomas E.

In: Chemistry of Materials, Vol. 8, No. 8, 01.01.1996, p. 2121-2127.

Research output: Contribution to journalArticle

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