Fortnightly seminars online: Dielectric Materials for Electrical Energy Storage by Qi Zhang

Dielectric Materials for Electrical Energy Storage Antiferroelectric (AFE) ceramics have shown great potential for applications in pulsed power capacitors because of their fast charge-discharge rates (on the order of nanoseconds). However, to date, it has been proven very difficult to simultaneously obtain large recoverable energy densities Wre and high energy efficiencies η in one type of ceramic, which limits the range of applications of these materials. Addressing this problem requires the development of ceramic materials that simultaneously offer a large ferroelectric-antiferroelectric (FE-AFE) phase-switching electric field E_A, high electric breakdown strength E_b, and narrow polarization-electric field (P-E) hysteresis loops. In this work, via doping of La³⁺ into (Pb_1-1.5xLa_x)(Zr_0.5Sn_0.43Ti_0.07)O₃ AFE ceramics, large E_A and E_b due to respectively enhanced AFE phase stability and reduced electric conductivity, and slimmer hysteresis loops resulting from the appearance of the relaxor AFE state, are successfully obtained, and thus leading to great improvement of the Wre and η. Besides, both Wre and η change very little in the temperature range of 25–125 °C.   The seminar will be online due to COVID restrictions. https://teams.microsoft.com/l/meetup-join/19%3ameeting_M2Y5OWYyMGUtOTQxOS00NTZmLWI0NzQtMjU1MGRlZDQ4ZjQx%40thread.v2/0?context=%7b%22Tid%22%3a%222f54ab68-83af-4d70-8895-a0d1e95ec899%22%2c%22Oid%22%3a%227778b4e1-e06d-485b-b530-cf013d4e9498%22%2c%22IsBroadcastMeeting%22%3atrue%7d&btype=a&role=a