76. A-site acceptor doped LaNbO4 thin film formation and structural investigation
Kristina Bockute1, Darius Virbukas2, Giedrius Laukaitis3
Physics Department, Kaunas University of Technology, Studentu 50, LT-51368 Kaunas, Lithuania
E-mail: email@example.com, firstname.lastname@example.org, email@example.com
(Received 7 October 2015; received in revised form 10 December 2015; accepted 21 December 2015)
Abstract. In this paper, doped La1-xAxNbO4
(A = Ca, Mg) thin films were formed using electron beam vapor
deposition. The influence of the doping concentration of A site dopants (A =
Ca, Mg) on the thin ceramics surface microstructure, morphology and
electrical properties, including the charge carrier mobility and diffusion
coefficient, was studied. It was found that the formed thin films are dense
(>96 %) and have homogenous nanocrystalline structure composed of the
tetragonal LaNbO4 phase. The total conductivity of the formed thin
films is in 10-3 S/cm range for Ca-doped LaNbO4 and 10-4
S/cm range for Mg-doped LaNbO4 at 800 °C under wet H2
reducing atmosphere. The nature of protonic conduction was confirmed by the
isotopic effect. The calculated is 57 kJ/mol at 650 °C for the La0.995Ca0.005NbO4
film, which total conductivity was highest in the present study (9.52∙10-3
S/cm at 800 °C under wet H2 reducing atmosphere). increases steadily with increasing the dopants’ concentration from
57 kJ/mol to 84 kJ/mol. The charge mobility decreases from 2.32×10-5 cm2/V∙s
Keywords: electron beam evaporation, nanocrystalline, proton conducting fuel cells (PCFC), doped lanthanum niobium oxide, LaNbO4.
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Cite this article
Bockute Kristina, Virbukas Darius, Laukaitis Giedrius A‑site acceptor doped LaNbO4 thin film formation and structural investigation. Journal of Measurements in Engineering, Vol. 3, Issue 4, 2015, p. 105‑113.
Journal of Measurements in Engineering. December 2015, Volume 3, Issue 4
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