Abstract—LLead free piezoelectric single crystals of sodium potassium niobate (K0.5Na0.5)NbO3 and 0.5wt%, 1wt%, 1.5wt% of copper oxide CuO doped sodium potassium niobate(K0.5Na0.5)NbO3 (KNN) single crystals were grown by hightemperature solution method and the dielectric properties, morphology and domain pattern were investigated. The flux used during crystal growth is eutectic mixture of potassium carbonate K2CO3 and sodium carbonate Na2CO3. Additions of small amounts of boron oxide B2O3 further lower the melting temperature of the eutectic mixture. It was found that 1.5wt% CuO doped single crystals of sodium potassium niobate exhibits excellent dielectric properties. XRD results showed sharp peaks indicating good crystalline behavior of both pure and CuO doped KNN crystals. Phase analysis showed that all samples crystallized in pure orthorhombic perovskite phase. A slight decrease in the diffraction angles has been observed with increase in doping concentration. This is due to the replacement of Nb5+ ions by Cu2+ ions, leading to the formation of higher oxygen vacancies with the doping concentrations.

Index Terms—Dielectric, domain, KNN, piezoelectric, single crystal etc.

R. Saravanan and M. Chitra are with Crystal Growth Centre, Anna University, Chennai
D. Rajesh is with G.T. Sollar Cell, China
S. V. Rajasekaran is with Govement Arts and Science College, Dharmapuri
R. Peurmal is with KTH, Sweden
R. Jayavel is with Crystal Growth Centre, Anna University, Chennai and Centre for Nanoscience and Technology, Anna University, Chennai (Corresponding author. Tel.: + 91-44-2235 8328, fax: +91-44-2230 1656, e-mail address: rjvel@annuni.edu).

Cite: R. Saravanan, D. Rajesh, S. V. Rajasekaran, R. Peurmal, M. Chitra, and R. Jayavel, "Effects of Copper Oxide Doping on the Properties of Sodium Potassium Niobate (Na0.5K0.5) NbO3 Piezoelectric Single Crystals Grown by Flux Method," International Journal of Applied Physics and Mathematics  vol. 2, no. 4, pp. 256-259, 2012.