In this paper the influence of Cu on dielectric and piezoelectric properties of K1/2Na1/2NbO3 (KNN) was evaluated. Samples were obtained by solid state reaction doping with CuO (0 to 2 mol%). The obtained samples were characterized by the Archimedes method, X-Ray diffraction, Raman spectroscopy, Scanning Electron Microscopy, polarization curves, piezoelectric constant (d33) and impedance spectroscopy at room temperature. In general, it was observed that doping does not improve dielectric and piezoelectric properties. Small amounts of CuO (0.5 mol%) slightly affected the densification process, while high concentrations increased the porosity of the samples. Also, low concentrations of CuO drastically reduced d33 values, presumably due to the hardening effect of the additive.
Piezoelectric materials; lead free; K1/2Na1/2NbO3
