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Title: Enhanced energy storage density in Sc3+ substituted Pb(Zr0.53Ti0.47)O3 nanoscale films by pulse laser deposition technique
Highly oriented Pb(Zr0.53Ti0.47)0.90Sc0.10O3 (PZTS) thin films were deposited on La0.67Sr0.33MnO3 (LSMO) buffer layer coated on MgO (100) substrates by following two subsequent laser ablation processes in oxygen atmosphere employing pulse laser deposition technique. The PZTS films were found to grow in tetragonal phase with orientation along (100) plane as inferred from x-ray diffractometry analysis. The structural sensitive symmetric E (LO2) Raman band softened at elevated temperature along with its intensity continuously decreased until it disappeared in the cubic phase above 350 K. The existence of broad Raman bands at high temperature (>350 K) is attributed to the symmetry forbidden Raman scattering in relaxor cubic phase due to symmetry breaking in nano length scale. The temperature dependent dielectric measurements were performed on metal-ferroelectric-metal capacitors in the frequencies range of 102–106 Hz was observed to be diffused over a wide range of temperature 300–650 K and exhibits high dielectric constant ~5700 at room temperature. An excellent high energy storage density (Ure) ~54 J/cm3 with efficiency ~70% was estimated at applied voltage 1.82 MV/cm. High DC breakdown strength, larger dielectric constant and high restored energy density values of our PZTS thin films indicate its usage in high energy storage applications.
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Applied surface science
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National Science Foundation
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