Effects of Li 2 CO 3 on the sintering temperature, microstructure, and electrical properties of PZT-PMnSbN relaxor ceramics

0.9Pb(Zr 0.49 Ti 0.51 )O 3 −0.1Pb[(Mn 1/3 Nb 2/3 ) 0.7 (Sb 1/2 Nb 1/2 ) 0.3 ]O 3 + x wt% Li 2 CO 3 (PZT–PMnSbN, x = 0.0, 0.2, 0.4, 0.6, 0.8, and 1.0) ceramics were by the two-step sintering method. It was found that the PZT-PMnSbN ceramic with a Li 2 CO 3 content of 0.6 wt% consisted of uniform particles with an average size of 1.62 μm and has a high mechanical quality coefficient ( Q m ) of 2050, a low dielectric loss (tan δ ) of 0.003), and a high Curie temperature of ( T C ) of 325 °C at a low sintering temperature of 950 °C. In addition, at the optimized Li 2 CO 3 content, the electrical properties of the Li 2 CO 3 -doped PZT-PMnSbN ceramics were significantly improved (dielectric constant = 1547, maximum dielectric constant = 22,500, electromechanical coupling factor ( k p ) = 0.62, piezoelectric coefficient ( d 33 ) = 340 pC/N, remanent polarization ( P r ) = 26.9 µC/cm 2 , and maximum strain ( S max ) = 0.15%). This research provides valuable insights to improve the low sintering temperature and electrical properties of materials for applications requiring high-temperature stability.