Enhanced energy density with a wide thermal stability in epitaxial Pb0.92La0.08Zr0.52Ti0.48O3 thin films

• Published in: Applied physics letters 2016-11, Vol.109 (19)
• Main Authors: Hu, Guangliang, Ma, Chunrui, Wei, Wei, Sun, Zixiong, Lu, Lu, Mi, Shao-Bo, Liu, Ming, Ma, Beihai, Wu, Judy, Jia, Chun-lin
• Format: Article
• Language: English
• Subjects: Applied physics; Columnar structure; Crystal defects; Energy storage; Epitaxy; Film thickness; Flux density; Grain boundaries; Lead lanthanum zirconate titanate; Pulsed laser deposition; Pulsed lasers; Strontium titanates; Substrates; Temperature; Temperature dependence; Thermal stability; Thin films; Transmission electron microscopy; X-ray diffraction
• ISSN: 0003-6951; 1077-3118
• DOI: 10.1063/1.4967223

High-quality epitaxial Pb0.92La0.08Zr0.52Ti0.48O3 (PLZT) films of thickness of ∼880 nm were fabricated using pulsed laser deposition on (001) Nb doped SrTiO3 (Nb:STO) substrates. Besides a confirmation of the epitaxial relationship [100]PLZT//[100]Nb:STO and (001)PLZT//(001)Nb:STO using X-ray diffraction, a transmission electron microscopy study has revealed a columnar structure across the film thickness. The recoverable energy density (Wrec ) of the epitaxial PLZT thin film capacitors increases linearly with the applied electric field and the best value of ∼31 J/cm3 observed at 2.27 MV/cm is considerably higher by 41% than that of the polycrystalline PLZT film of a comparable thickness. In addition to the high Wrec value, an excellent thermal stability as illustrated in a negligible temperature dependence of the Wrec in the temperature range from room temperature to 180 °C is achieved. The enhanced Wrec and the thermal stability are attributed to the reduced defects and grain boundaries in epitaxial PLZT thin films, making them promising for energy storage applications that require both high energy density, power density, and wide operation temperatures.