Enhanced electrical properties with high Curie temperature in PMN‒PZT single crystal by solid‐state crystal growth

Abstract 0.25 Pb(Mg 1/3 Nb 2/3 )O 3 ‒0.35PbZrO 3 ‒0.40PbTiO 3 (PMN‒PZT) single crystals were successfully grown by solid‐state crystal growth (SSCG) method. The microstructure, phase structure, dielectric, ferroelectric, piezoelectric, and electromechanical properties were systematically investigated for the [110]/[001]‐oriented PMN‒PZT single crystals and compared with those of composed ceramics. Most notably, the [001]‐oriented PMN‒PZT single crystals possess high piezoelectric properties ( d 33 ∼ 1098 pC/N), high piezoelectric voltage constant ( g 33 ∼ 62 × 10 −3 V m/N), ultra‐high figure of merit ( g 33 × d 33 ∼ 68 × 10 −12 m 2 /N), excellent electromechanical coupling coefficient ( k 33 ∼ 0.88), high Curie temperature ( T C ∼ 313°C), and rhombohedral to tetragonal phase transition temperature ( T R‐T ∼ 154°C). Moreover, the is 1468 pm/V at room temperature and can reach 4215 pm/V at 160°C under a low electric field of 5 kV/cm. The k 33 is stable around 0.88 in range of room temperature to around 140°C. This work extends the composition range of single crystal growth in PMN‒PZT system by SSCG method and the PMN‒PZT single crystals exhibit significant application potential in piezoelectric actuator, energy harvester, and electromechanical devices.