Electrical properties and impedance spectroscopy of pure and copper-oxide-added potassium sodium niobate ceramics
IEEE Transactions on Ultrasonics, Ferroelectrics, and Frequency Control, cilt.59, sa.10, ss.2121-2128, 2012 (SCI-Expanded, Scopus)
- Yayın Türü: Makale / Tam Makale
- Cilt numarası: 59 Sayı: 10
- Basım Tarihi: 2012
- Doi Numarası: 10.1109/tuffc.2012.2438
- Dergi Adı: IEEE Transactions on Ultrasonics, Ferroelectrics, and Frequency Control
- Derginin Tarandığı İndeksler: Science Citation Index Expanded (SCI-EXPANDED), Scopus
- Sayfa Sayıları: ss.2121-2128
- Maltepe Üniversitesi Adresli: Evet
Özet
Pure and 1 mol% CuO-added lead-free potassium sodium niobate K 0.5Na0.5NbO3 (KNN) ceramics were prepared by the conventional solid-state calcination method. Copper oxide was mainly used as a sintering aid in the KNN structure. Microstructural analyses clearly showed that the CuO formed a secondary phase at the grain boundaries. Impedance spectroscopy was used as a tool to analyze the electrical behavior of KNN ceramics as a function of frequency from 100 Hz to 10 MHz at various temperatures. The impedance studies proved that CuO led to the formation of a secondary grain boundary phase, as well as creation of highly mobile point defects. The relaxation time of copper-added samples was less than that of pure KNN. This shorter time indicated a higher space charge mobility for CuO-added samples. The thermal activation energy for relaxation of charge carriers (E g) was calculated as 0.73 eV for CuO-added samples. © 1986-2012 IEEE.