Tailoring electrical properties and thermal stability of PNT-PZT ceramics via Mn doping

This study presents a comprehensive investigation of the structural, dielectric, and piezoelectric properties of Mn-doped 0.12PNT-0.88PZT ceramics. X-ray diffraction (XRD) confirms the formation of pure perovskite tetragonal phases in all compositions. The incorporation of Mn exerts a pronounced influence on the functional properties of the ceramics, including dielectric, ferroelectric and piezoelectric properties etc. Notably, the 1.5 mol% Mn-doped 0.12PNT-0.88PZT composition demonstrates enhanced performance, achieving ɛ_r = 2838, P_r = 15.2 μC/cm², d₃₃ = 440 pC/N, while the 2.5 mol% Mn-doped variant achieves an exceptional Q_m of 730. Rayleigh analysis of the dielectric response reveals that the extrinsic contribution, quantified by the Rayleigh parameter (α), peaks at a Mn doping concentration of 1.5 mol%. These findings indicate that as extrinsic effects intensify, domain switching and grain boundary contributions to the electrical properties become increasingly dominant. Furthermore, the 1.5 mol% Mn-doped 0.12PNT-0.88PZT ceramics demonstrate excellent temperature stability in piezoelectric coefficient, electromechanical coupling factor, and mechanical quality factor over a broad temperature range from the room temperature to 120 °C. This work provides critical insights into the role of Mn doping in enhancing the functional properties of PNT-PZT ceramics and highlights its potential for applications requiring stable performance under varying thermal conditions.