Improved Curie temperature, electromechanical properties and thermal stability in ZnO-modified 0.68Pb(Mg1/3Nb2/3)O3-0.32PbTiO3 ceramics with coexisting monoclinic and tetragonal phases

Further improving electromechanical properties and overcoming relatively low Curie temperature (T-c) of (1-x) Pb(Mg1/3Nb2/3)O-3-xPbTiO(3) (PMN-100xPT) are still two scientific issues. Here, we demonstrate a stable coexistence of monoclinic -tetragonal (Mc -T) phases in ZnO-modified PMN-32PT (PMN-32PT:xZnO) due to the diffusion -induced substitution of Zn2+ for Mg2+. The Curie temperature, saturated polarization, remnant polarization, piezoelectric coefficient (T-c, P-s, P-r, d(33)) are increased from (160 degrees C, 22.0 mu C/cm(2), 13.3 mu C/cm(2), 350 pC/ N) for x = 0 to (180 degrees C, 30.3 mu C/cm(2), 22.4 mu C/cm(2), 470 pC/N) for x = 0.06. Moreover, the thermal stability is improved. After annealing at 150 degrees C, the x = 0.06 sample shows retrained d(33) value of 209 pC/N, about 4 times larger than that of x = 0 counterpart. The improved properties are attributed to the substituting increased polar nanoregions and easy domain switching in M-c phase.