Tuning the microstructure of BaTiO3@FeO core-shell nanoparticles with low temperatures sintering dense nanocrystalline ceramics for high energy storage capability and stability

A BaTiO3@FeO nanoceramic was successfully fabricated by chemical coating technique under sintering and achieved high energy storage capability. The FeO layer was coated onto BaTiO3 nanoparticles by sol-precipitation method. The structures, dielectric properties and energy storage capability of ceramics were systematically investigated. A high densification and nano-scale crystalline were observed after low temperatures sintering by this chemical coating technology and the grain size maintained about 70 nm. This chemical coating method is contributed to obtain dense nanocrystalline ceramics, benefiting to enhance the breakdown strength and energy storage density. The dielectric properties of BaTiO3@%FeO nanoceramics exhibit good temperature (−55 to 125 °C) and frequency(1 Hz–1 MHz) stability, indicating the fine dielectric quality of the ceramics. The BaTiO3@3%FeO nanoceramics present a high discharge energy storage density of 1.50 J cm−3 at 300 kV/cm-1 with a high energy storage efficiency about 88%. Moreover, the advanced energy storage properties with fast discharge features (τ0.9< 1.5 μs), prominent thermal stability (25–120 °C) and high cyclic stability (up to 1 × 105 times) were achieved in the BaTiO3@FeO nanoceramic. This nanoceramic prepared via the chemical coating could be a potential material for energy storage capacitor application.