Pb, Bi, and rare earth free X6R barium titanate–sodium niobate ceramics for high voltage capacitor applications

0.9Ba(Ti 1−x Mg x )O 3−x -0.1NaNbO 3 (BTNN-100xMg) solid solutions are investigated with a view to developing Bi, Pb, and rare earth free, high voltage multilayer ceramic capacitors. doping on the B-site significantly reduced electronic conductivity resulted in ceramics that could withstand pulsed unipolar field of >300 kV/cm (E max ) give recoverable energy density 3.4 J/cm at 82.6% efficiency for = 0.01. The E is accompanied by dielectric permittivity (ε′ ∼ 1700 room temperature) temperature-stable Δε/ε 298K ≤ ±15% loss tangent tan δ < 0.02 from 116 378 K, corresponding an X6R designation Electronic Industry Alliance codes.