Impact of Gd-doping on structural and electrical properties of 0.4CaBi2Nb2O9-0.6Na0.5Bi2.5Nb2O9 piezoelectric ceramics.

This paper focuses on improving the electrical properties of 0.4CaBi 2 Nb 2 O 9 -0.6Na 0.5 Bi 2.5 Nb 2 O 9 piezoelectric ceramics through Gd doping. The effect of Gd3+ replacing Ca2+ and Na+ on the 0.4CaBi 2 Nb 2 O 9 -0.6Na 0.5 Bi 2.5 Nb 2 O 9 (0.4CBN-0.6NBN) piezoelectric ceramics was subjected to a comprehensive examination. The introduction of Gd3+ has led to the development of a pseudo-tetragonal phase, enhancing the polarization and strengthening the piezoelectric effect. Among the 0.4CBN-0.6NBN- x Gd (x = 0.00–0.05) ceramic samples, the sample at x = 0.03 that exhibits the best piezoelectric properties demonstrates a high Curie temperature of 849.7 °C, low dielectric loss (tan δ) of 1.295 % (at 550 °C), high DC resistivity (ρ DC) of 1.58 × 108 Ω‧cm (at 500 °C), and a high d 33 value of 17.3 pC/N. Following annealing at 800 °C, its d 33 retains 94.2 % of its initial value. The improved electrical performances indicate that the Gd-doped 0.4CBN-0.6NBN ceramics hold a great deal of promise for high-temperature piezoelectric applications. [ABSTRACT FROM AUTHOR]