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arXiv · 2110.02659

Structural, electrical and energy storage properties of lead-free NaNbO3-BaHfO3 thin films

Huijuan Dong·Bingcheng Luo·Kexin Jin
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Abstract

Lead-free dielectric thin-film capacitors with desirable energy storage density are gathering attention due to the increasing environmental concern and the integrating electronic devices. We here reported a series of new highly-orientated (1-x)NaNbO3-xBaHfO3 (x<0.15) lead-free thin films prepared by a sol-gel method, and presented the dependence of their structural, electrical and energy storage properties on the x level of BaHfO3. The microstructure, leakage current and breakdown strength of pristine NaNbO3 thin films are significantly improved by addition of BaHfO3. As a result, the superior energy storage performances were obtained at x=0.1 with recoverable energy storage density of 23.1 J/cm3 at 1100 kV/cm, excellent thermal stability from 30 to 210 0C, good fatigue resistance, and the fast charge-discharge rate.

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Huijuan Dong, Bingcheng Luo, Kexin Jin. 2021-10-06. Structural, electrical and energy storage properties of lead-free NaNbO3-BaHfO3 thin films. https://doi.org/10.1016/j.jpcs.2021.110513

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