Synergistic phase and defect engineering for enhanced piezoelectric and high-power performance in Mn/Nb-modified Pb(Zr0.5Ti0.5)O3-Pb(Mn1/3Nb2/3)O3 ceramics

High-power piezoelectric ceramics require both a high piezoelectric coefficient and a large vibration output. Yet, simultaneous optimization remains challenging because of the intrinsic coupling between polarization activity and mechanical loss. Here, Mn/Nb ratio engineering was applied to 0.9 Pb(Zr 0.5 Ti 0.5 )O 3 -0.1 Pb(Mn 1/3 Nb 2/3 )O 3 -0.01Co 3 O 4 -0.001Fe 2 O 3 (PZT-PMN) ceramics to regulate phase structure and electromechanical properties. An optimized R3m/Cm/P4mm multiphase coexistence was achieved through composition tuning, together with regulated grain growth and polarization behavior. At a Mn/Nb ratio of 0.4, the ceramic exhibits a superior piezoelectric coefficient ( d 33  = 420 pC/N), electromechanical coupling factor ( k p  = 0.62), and mechanical quality factor ( Q m  = 1608), along with stable d 33 variation <5% from 25 to 275 °C and a maximum vibration velocity of 0.57 m/s, exceeding that of commercial PZT4 under identical conditions. The enhanced performance is associated with the coupled regulation of defect chemistry, phase coexistence, and domain-wall dynamics. A composition-driven strategy for balancing piezoelectric activity and high-power output in PZT-based ceramics is identified.