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

TL;DR

This study develops lead-free NaNbO3-BaHfO3 thin films with enhanced energy storage density and stability, demonstrating promising potential for environmentally friendly electronic energy storage applications.

Contribution

It introduces a new series of highly-oriented lead-free NaNbO3-BaHfO3 thin films with optimized energy storage properties using a sol-gel method.

Findings

Achieved a recoverable energy storage density of 23.1 J/cm3 at x=0.1.

Improved microstructure, leakage current, and breakdown strength with BaHfO3 addition.

Demonstrated excellent thermal stability and fatigue resistance.

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.