Ferroelectric and pyroelectric properties of Mn-doped lead zirconate titanate ceramics

PbNb0.02(Zr0.95Ti0.05)0.98O3 (PNZT95/5) ceramics with Mn doping were prepared and the effects of Mn doping on the phase structure and electrical properties were investigated. It was found that Mn addition did not cause a remarkable change in rhombohedral perovskite structure, but significantly altered ferroelectric and pyroelectric properties of the PNZT95/5 ceramics. PNZT95/5 ceramics usually possessed a normal single hysteresis loop character when no aging process was employed, whereas Mn doped PNZT95/5 (PNMZT95/5) ceramics exhibited a double-hysteresis-like loop character because of the defect dipoles formed by Mn2+ and O2− vacancies. Meanwhile, ferroelectric features such as the polarization and coercive field showed a strong frequency and temperature dependence. Furthermore, Mn substitution resulted in the weakened dielectric property and enhanced pyroelectric property of the ceramics. The relevant pyroelectric coefficient (p) and detectivity figure of merit (FD) increased from 7.90×10−8 to 9.15×10−8 C cm−2 K−1 and 8.69×10−5 to 16.74×10−5 Pa−1/2, respectively, which make the PNMZT95/5 ceramics potential application in commercial infrared detectors.