Dielectric Properties of New Cd_1-3xDy_2x[]_xMoO₄ Molybdates (where 0 < x ≤ 0.2)

Abstract:

New scheelite type Cd_1-3xDy_2x[]_xMoO₄ solid solution, where 0.0098 ≤ x ≤ 0.2 and [] denotes the cationic vacancies, was investigated by using UV-vis-NIR and dielectric spectroscopies at room temperature and in the temperature range 77-400 K, respectively. These studies showed the optical band gap energy E_g above 3.4 eV and relative low dielectric permittivity: ε_r ~ 6.0, 9.5, 7.0 and 8.2 for the x parameter 0.0098, 0.0839, 0.1667 and 0.2000, respectively. ε_r slightly decreases with increasing frequency and slightly increases at higher temperatures. All samples showed the maximum permittivity in the temperature range of 250-350 K. The loss tangent exhibited similar behaviour and its maximum value did not exceed 0.25. These results are discussed in a context of the shallow trap levels and the Maxwell-Wagner model.

• Periodical: Solid State Phenomena (Volume 257)
• Pages: 103-106
• DOI: https://doi.org/10.4028/www.scientific.net/SSP.257.103
• Online since: October 2016
• Authors: Piotr Urbanowicz, Magdalena Piątkowska, Marta Pawlikowska, Elzbieta Tomaszewicz, Henryk Duda, Tadeusz Groń*
• Keywords: Dielectric Spectroscopy, Scheelite Structure, UV-vis-NIR Spectroscopy

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