An Energy Storage Material Fabricated by Coating Ba_(0.40)Sr_(0.60)TiO_3 Nano Particles with Aluminum Oxide Doped with Zinc Oxide Shell

摘要

For energy storage devices such as capacitances, pulsed power applications and other any electronic systems, high permittivity and high breakdown strength (BDS) are necessary for dielectric materials used in high energy storage capacitors. Ba_(0.4)Sr_(0.6)TiO_3 nano-powders were directly synthesized from solution and then wrapped by a thin surrounding shell with composition of zinc oxides dopants in aluminum oxides. This core-shell structure was characterized by a conjunction of XRD, and TEM analysis. The core-shell nanoparticles were pressed into pellets with 10 mm diameter and then sintered at different temperature in air. The specimen coated with 2.0wt% compounds of aluminum oxides doped with zinc oxides showed the maximum breakdown strength of 475kV/cm, energy storage density of 4.7J/cm~3, and low tanδ of only 0.002.Whereas, the uncoated Ba_(0.4)Sr_(0.6)TiO_3 was only 86.9kV/cm,0.23J/cm~3 and 0.005, respectively. And the energy storage density and the BDS decreased when the shell content was more than 2.0wt%.