Anti-reduction resistance mechanism and energy storage performance analysis for Mg2+ doped BaTiO3-based ceramics produced in reducing atmosphere

The development of base metal electrode multilayer ceramic capacitor (BME-MLCC) dielectric materials that combine high reduction resistance with superior energy storage performance is crucial to meet the demands of next-generation high-power electronic devices and power modules. In this study, a series of BaTiO 3 –MnO 2 –Yb 2 O 3 – x MgO (BMYT- x Mg, x  = 0–3) ceramics were successfully produced in a reducing atmosphere. The influence of Mg 2+ acceptor doping on the anti-reduction resistance mechanism and energy storage behavior was systematically investigated. The results indicate that Mg 2+ doping promotes the formation of [Mgʹʹ Ti-V•• O] defect dipoles, which effectively suppresses the generation and migration of charge carriers. This mechanism enables the BMYT-2Mg ceramic to maintain an insulation resistivity as high as 3.6 × 10 11  Ω m even after sintering in a reducing atmosphere. Additionally, Mg 2+ doping optimizes the phase structure, refines the grain size, increases the grain boundary density, and synergistically enhances the relaxor characteristics of the system. As a result, the BMYT-2Mg ceramic achieves a recoverable energy storage density ( W rec ) of 1.75 J/cm 3 and an energy storage efficiency ( η ) of 72.65% under an electric field of 270 kV/cm. It also demonstrates excellent energy storage stability and electrical reliability across a temperature range of 40–120 °C and over 10 5 charge–discharge cycles at 130 kV/cm. This work provides an effective design strategy for fabricating BaTiO 3 -based dielectric ceramics with both high reduction resistance and superior energy storage performance in a reducing atmosphere.