High Energy Density Piezoelectric Ceramics for Energy Harvesting Devices

The ceramics, (0.65 + y ) Pb ( Zr 0.47 Ti 0.53 )–(0.35 − y ) Pb [( Ni 1− x Zn x ) 1/3 Nb 2/3 ] O 3 have a morphotropic phase boundary ( MPB ) of pseudo‐cubic and tetragonal structures. Their ε 33 T /ε 0 value considerably decreased on the pseudo‐cubic side of the MPB composition, but the d 33 and k p slowly decreased on both sides of the MPB . Therefore, the maximum transduction coefficient ( d 33 * g 33 ) was obtained from the composition on the pseudo‐cubic side of the MPB , because g 33 is given by d 33 /ε 33 T . This result could be applied to other systems containing an MPB of pseudo‐cubic and tetragonal structures. Furthermore, a d 33 * g 33 value of 20 056 × 10 −15 m 2 /N, which is the highest value reported so far for polycrystalline ceramics, was obtained from the 0.68 Pb ( Zr 0.47 Ti 0.53 ) O 3 –0.32 Pb ( Ni 0.6 Zn 0.4 ) 1/3 Nb 2/3 O 3 ceramic.