abstract
Lead-free 0.5BaZr(0.2)Ti(0.8)O(3)-0.5Ba(0.7)Ca(0.3)TiO(3) (BZT-BCT) thin films were deposited on Pt(1 1 1)/TiO2/SiO2/Si substrates by pulsed laser deposition. The optimal ferroelectric response with a high saturation polarization P-s similar to 110 mu C cm(-2), remnant polarization P-r similar to 32.5 mu C cm(-2) along with a coercive field of 0.18 MV cm(-1) was observed from the P-E hysteresis loops under an applied frequency of 1 kHz. A giant recoverable energy-storage density of 93.52 J cm(-3) at an applied electric field similar to 3.47 MV cm(-1) was observed. The optimized BZT-BCT thin films exhibited a high dielectric constant with a low dielectric loss at room temperature like their bulk counterpart (high dielectric constant (epsilon similar to 121 81)) and low dielectric loss (tan delta similar to 0.01-0.03) properties. OPP-PFM images revealed switchable ferroelectric distinct polarization contrasts on the application of a +/- 12 V dc voltage on the conductive tip at room temperature. Observed enhanced dielectric, ferroelectric and energy density properties of BZT-BCT thin films are useful for next generation electrical energy storage applications.
keywords
DIELECTRIC-PROPERTIES; PHASE-TRANSITION; DENSITY; CAPACITORS; NANOCOMPOSITES; DEPOSITION; BEHAVIOR
subject category
Physics
authors
Puli, VS; Pradhan, DK; Coondoo, I; Panwar, N; Adireddy, S; Luo, SJ; Katiyar, RS; Chrisey, DB
our authors
acknowledgements
This work was supported by the NSF-EFRI Award #1038272 grant. One of the authors (I C) would like to acknowledge funding by national funds (O E), through FCT-Fundacao para a Ciencia e a Tecnologia, I.P., in the scope of the framework contract foreseen in the numbers 4, 5 and 6 of the article 23, of the Decree-Law 57/2016, of August 29, changed by Law 57/2017, of July 19.