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Title: The luminescence of BaF{sub 2} nanoparticles upon high-energy excitation

Abstract

The dependence of X-ray excited luminescence intensity on BaF{sub 2} nanoparticle size was studied. A sharp decrease of self-trapped exciton luminescence intensity was observed when the nanoparticle size is less than 80 nm. The main mechanism of the luminescence quenching is caused by the escape of electrons from the nanoparticles. Escape of electrons from nanoparticles is confirmed by the considerable increase of luminescence intensity of the polystyrene scintillator with embedded BaF{sub 2} nanoparticles comparing with pure polystyrene scintillator.

Authors:
; ; ;  [1]; ;  [2];  [3];  [4];  [5]
  1. Ivan Franko National University of Lviv, 8a Kyryla i Mefodiya St., 79005 Lviv (Ukraine)
  2. Lviv Polytechnic National University, 12 S. Bandera St., 79013 Lviv (Ukraine)
  3. Saint-Petersburg State Polytechnical University, 29, Polytekhnicheskaya, 195251 Saint-Petersburg (Russian Federation)
  4. Skobeltsyn Institute of Nuclear Physics, Lomonosov Moscow State University, 119991 Moscow (Russian Federation)
  5. Institute for Scintillation Materials, NAS of Ukraine, 60 Lenina Ave, 61001 Kharkiv (Ukraine)
Publication Date:
OSTI Identifier:
22314704
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Applied Physics; Journal Volume: 116; Journal Issue: 5; Other Information: (c) 2014 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; BARIUM FLUORIDES; COMPARATIVE EVALUATIONS; EXCITATION; LUMINESCENCE; NANOPARTICLES; POLYSTYRENE; QUENCHING; TRAPPING; X RADIATION

Citation Formats

Vistovskyy, V. V., E-mail: visvv@gmail.com, Zhyshkovych, A. V., Halyatkin, O. O., Voloshinovskii, A. S., Mitina, N. E., Zaichenko, A. S., Rodnyi, P. A., Vasil'ev, A. N., and Gektin, A. V.. The luminescence of BaF{sub 2} nanoparticles upon high-energy excitation. United States: N. p., 2014. Web. doi:10.1063/1.4892112.
Vistovskyy, V. V., E-mail: visvv@gmail.com, Zhyshkovych, A. V., Halyatkin, O. O., Voloshinovskii, A. S., Mitina, N. E., Zaichenko, A. S., Rodnyi, P. A., Vasil'ev, A. N., & Gektin, A. V.. The luminescence of BaF{sub 2} nanoparticles upon high-energy excitation. United States. doi:10.1063/1.4892112.
Vistovskyy, V. V., E-mail: visvv@gmail.com, Zhyshkovych, A. V., Halyatkin, O. O., Voloshinovskii, A. S., Mitina, N. E., Zaichenko, A. S., Rodnyi, P. A., Vasil'ev, A. N., and Gektin, A. V.. Thu . "The luminescence of BaF{sub 2} nanoparticles upon high-energy excitation". United States. doi:10.1063/1.4892112.
@article{osti_22314704,
title = {The luminescence of BaF{sub 2} nanoparticles upon high-energy excitation},
author = {Vistovskyy, V. V., E-mail: visvv@gmail.com and Zhyshkovych, A. V. and Halyatkin, O. O. and Voloshinovskii, A. S. and Mitina, N. E. and Zaichenko, A. S. and Rodnyi, P. A. and Vasil'ev, A. N. and Gektin, A. V.},
abstractNote = {The dependence of X-ray excited luminescence intensity on BaF{sub 2} nanoparticle size was studied. A sharp decrease of self-trapped exciton luminescence intensity was observed when the nanoparticle size is less than 80 nm. The main mechanism of the luminescence quenching is caused by the escape of electrons from the nanoparticles. Escape of electrons from nanoparticles is confirmed by the considerable increase of luminescence intensity of the polystyrene scintillator with embedded BaF{sub 2} nanoparticles comparing with pure polystyrene scintillator.},
doi = {10.1063/1.4892112},
journal = {Journal of Applied Physics},
number = 5,
volume = 116,
place = {United States},
year = {Thu Aug 07 00:00:00 EDT 2014},
month = {Thu Aug 07 00:00:00 EDT 2014}
}
  • The influence of the BaF{sub 2} nanoparticle size on the intensity of the self-trapped exciton luminescence and the radiative core-valence transitions is studied by the luminescence spectroscopy methods using synchrotron radiation. The decrease of the self-trapped exciton emission intensity at energies of exciting photons in the range of optical exciton creation (hν ≤ E{sub g}) is less sensitive to the reduction of the nanoparticle sizes than in the case of band-to-band excitation, where excitons are formed by the recombination way. The intensity of the core-valence luminescence shows considerably weaker dependence on the nanoparticle sizes in comparison with the intensity ofmore » self-trapped exciton luminescence. The revealed regularities are explained by considering the relationship between nanoparticle size and photoelectron or photohole thermalization length as well as the size of electronic excitations.« less
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