Dielectric characteristic of nanocrystalline Na0.5K0.5NbO3 ceramic green body

Laijun Liu (1, 2, 3) , Huiqing Fang (2) , Liang Fang (1) , Hichem Dammak (3, 4) , Maï Pham-Thi (5)

1 Key Laboratory of nonferrous Materials and New Processin Technology
2 State Key Laboratory of solidification processing
3 SPMS - Laboratoire Structures, Propriétés et Modélisation des solides
4 LSI - Laboratoire des Solides Irradiés - Irradiated Solids Laboratory
5 Thales Research and Technology [Palaiseau]

Dielectric spectroscopy was applied to porous nanocrystalline Na0.5K0.5NbO3 (NKN) ceramic green body, wherein influences of percolation effect and water adsorption at pore surface of the ceramic green body on dielectric response were examined over wide temperature (150 to 450 K) and frequency (100 Hz to 1 MHz) ranges. Dielectric permittivity of the ceramic green body is about 2-3 orders of magnitude higher than that of pure NKN powder or NKN ceramic. Furthermore, the high dielectric permittivity and high humidity sensitivity of the ceramic green body can appear again with aging a period of time in air. The data from this investigation make potential applications for NKN as a giant dielectric material or a humidity sensing material.

Domaines: Science des matériaux [cond-mat.mtrl-sci]

Laijun Liu, Huiqing Fang, Liang Fang, Hichem Dammak, Maï Pham-Thi. Dielectric characteristic of nanocrystalline Na0.5K0.5NbO3 ceramic green body. Journal of Electroceramics, 2012, 28, pp.144-148. ⟨10.1007/s10832-012-9695-6⟩. ⟨hal-00763823⟩