Novel BaTiO(3)-Based, Ag/Pd-Compatible Lead-Free Relaxors with Superior Energy Storage Performance

[Image: see text] Ceramic dielectrics are reported with superior energy storage performance for applications, such as power electronics in electrical vehicles. A recoverable energy density (W(rec)) of ∼4.55 J cm(–3) with η ∼ 90% is achieved in lead-free relaxor BaTiO(3)-0.06Bi(2/3)(Mg(1/3)Nb(2/3))O(3) ceramics at ∼520 kV cm(–1). These ceramics may be co-fired with Ag/Pd, which constitutes a major step forward toward their potential use in the fabrication of commercial multilayer ceramic capacitors. Compared to stoichiometric Bi(Mg(2/3)Nb(1/3))O(3)-doped BaTiO(3) (BT), A-site deficient Bi(2/3)(Mg(1/3)Nb(2/3))O(3) reduces the electrical heterogeneity of BT. Bulk conductivity differs from the grain boundary only by 1 order of magnitude which, coupled with a smaller volume fraction of conducting cores due to enhanced diffusion of the dopant via A-site vacancies in the A-site sublattice, results in higher breakdown strength under an electric field. This strategy can be employed to develop new dielectrics with improved energy storage performance.