Investigation of the structural and piezoelectric characteristics of (1-x)Pb (Zr, Ti)O3-xPb(Zn0.4Ni0.6)1/3Nb2/3O3 ceramics with R-PC-T multistructure

The structural and various electrical properties of (1-x)Pb(Zr1-zTiz)O3-xPb(Zn0.4Ni0.6)1/3Nb2/3O3 [(1-x)P(Z1-zTz)xPZNN] piezoceramics have been systematically investigated to ascertain the compositions that manifest a rhombohedral-pseudocubic-tetragonal (R-PC-T) multistructure. Rietveld refinement results indicate that the pseudocubic (PC) structure observed in the (1-x)P(Z1-zTz)-xPZNN piezoceramics closely resembles the Pm3m cubic structure. Nonetheless, the PC structure cannot be classified as cubic, given that piezoceramics exhibiting the PC structure also demonstrate ferroelectric and piezoelectric properties. The R-PC-T multistructure was detected in (1-x)P(Z1-zTz)-xPZNN piezoceramics for compositions where 0.335 <= x <= 0.44, across various z values. Compositions exhibiting the R-PC-T multistructure are identified as particularly promising. Notably, the piezoceramic with the composition 0.58 P(Z0.41T0.59)-0.42PZNN (x = 0.42 and z = 0.59) displayed remarkable piezoelectric properties, including a high piezoelectric charge constant, d33, of 825 pC/N, a coupling coefficient, kp, of 0.7, and a strain of 0.185% at 3.0 kV/mm, alongside a high Curie temperature (TC) of 240 degrees C.