Analysis of the structure and conductance of Mg2+ acceptor-doped CaBi2Nb2-Mg O9-3/2 piezoceramics

Enhanced piezoelectric performance in Na0.5Bi4.5Ti4O15‐based bismuth‐layered ceramics by Nb/Mn doping modification

“…We also compare our finding with other Na 0.5 Bi 4.5 Ti 4 O 15 ‐based bismuth layer piezoelectric ceramics, as shown in Figure 6D. It can be seen from Figure 6D that both the piezoelectric coefficient and Curie temperature of Na 0.5 Bi 4.5 Ti 3.94– x Mn 0.06 Nb x O 15+ y ceramics with x = 0.08 mol have an advantage over the state‐of‐the‐art bismuth layer piezoelectric ceramic materials, which have great potential application prospects in extremely harsh high‐temperature environments 2,24,34,36–55 …”

“…According to the XRD Rietveld refinement, the addition of Nb 5+ with larger radii (0.645 Å) into Na 0.5 Bi 4.5 Ti 4 O 15 ceramics to replace Ti 4+ with smaller radii (0.605 Å) causes the distortion of TiO 6 octahedral and reduction in barriers, giving rise to the decrease in free energy. Therefore, the Curie temperature of Na 0.5 Bi 4.5 Ti 3.94– x Mn 0.06 Nb x O 15+ y ceramics decreased slightly 30,34 . At the same time, the temperature‐dependent d 33 of Na 0.5 Bi 4.5 Ti 3.94– x Mn 0.06 Nb x O 15+ y ceramics in the temperature range of 25°C–450°C are presented in Figure 6C.…”

“…However, the P – E loops of Na 0.5 Bi 4.5 Ti 3.94– x Mn 0.06 Nb x O 15+ y ceramics still present lossy and asymmetrical shapes, which are closely related to the oxygen vacancy and defects. The oxygen vacancy and defects cannot keep up with the movements of dipoles; thus, asymmetrical and dissipated P – E loops are obtained 11,34 …”

“…(E) The contour plots of the Raman patterns. (F) The compositional dependence of Raman mode of Na 0.5 Bi 4.5 Ti 3.94-x Mn 0.06 Nb x O 15+y ceramicsdipoles; thus, asymmetrical and dissipated P-E loops are obtained 11,34.…”

“…(B) The relationship of d 33 , lattice constant b/a, and the Curie temperature with different Nb 5+ contents. (C) The temperature-dependent d 33 of Na 0.5 Bi 4.5 Ti 3.94-x Mn 0.06 Nb x O 15+y ceramics in the temperature range of 25 • C-450 • C. (D) The piezoelectric performance of Na 0.5 Bi 4.5 Ti 3.94-x Mn 0.06 Nb x O 15+y ceramics compared with other high-T c piezoelectric ceramicsbismuth layer piezoelectric ceramic materials, which have great potential application prospects in extremely harsh high-temperature environments 2,24,34,[36][37][38][39][40][41][42][43][44][45][46][47][48][49][50][51][52][53][54][55]. In summary, Na 0.5 Bi 4.5 Ti 3.94-x Mn 0.06 Nb x O 15+y ceramics were prepared by the conventional solid-state method.…”