Mechanical self-confinement to enhance energy storage density of antiferroelectric capacitors

The energy storage density of electrical capacitors utilizing antiferroelectric compositions Pb0.99Nb0.02[(Zr0.57Sn0.43)1−yTiy]0.98O3 as dielectrics is measured at a series of temperatures in a series of dielectric compositions with and without self-confinement. Under the applied electric field of 70 kV/cm, a maximum energy density of 1.3 J/cm3 is achieved. The mechanical self-confinement was introduced by partially electroding the central portion of the dielectric ceramic disk. A phase-field model was developed and it confirms the presence of compressive stresses ∼30 MPa in the electroded portion of the dielectric disk and the contribution to the increased energy density from the mechanical confinement.