Enhanced electrical properties in W/Cu co‐doped CaBi2Nb2O9 high‐temperature piezoelectric ceramics

Abstract CaBi 2 Nb 2 O 9 (CBN)‐based high‐temperature piezoelectric ceramics with the formula of CaBi 2 Nb 2− x (W 3/4 Cu 1/4 ) x O 9 were prepared via the traditional solid‐state reaction method. Both the bulk microstructure and the electrical performance of the W/Cu co‐doped CBN‐based ceramics were systematically investigated. The results indicated that the W/Cu incorporation into the Nb‐site altered the crystal structure, which enhanced the piezoelectricity and resistivity. The ceramic with the composition CaBi 2 Nb 1.96 (W 3/4 Cu 1/4 ) 0.04 O 9 exhibited good performance with a high d 33 (~14 pC/N) and T C (~939℃). Moreover, the ceramic exhibited a good electrical resistivity ( ρ ) of 4.91 × 10 5 Ω·cm and a low dielectric loss (tanδ) of 0.1 at 600℃. Furthermore, the ceramic that was annealed at 900℃ for 2 h presented a d 33 value of 13 pC/N, thus indicating good thermal stability of the piezoelectric properties. All these results confirm that the CaBi 2 Nb 1.96 (W 3/4 Cu 1/4 ) 0.04 O 9 ceramic may act as a potential promising candidate for piezoelectric device applications in high‐temperature environments.