Synergistic enhancement of breakdown and dielectric properties in ceramic dielectrics via in-situ carbon nanoparticle incorporation

Ceramic dielectrics play a vital role in advanced electronic systems. However, the relatively low breakdown strength restricts the further application of ceramic dielectrics. To address this challenge, a novel vapor-phase in - situ deposition strategy is proposed in this study to enhance the breakdown strength of ceramic dielectrics. Specifically, carbon nanoparticles are uniformly introduced into the barium titanate (BT) ceramic matrix via the co-sintering of carbon black and pre-calcined ceramics. In this design, the Coulomb blockade effect of carbon nanoparticles suppresses charge transport to improve breakdown strength, while the micro-capacitor effect simultaneously enhances the dielectric constant. Experimental results show that the breakdown strength and dielectric constant (at 1 kHz) of the BT-4C ceramics reach 16.98 kV/mm and 4581, respectively, marking substantial increases of 49.9% and 49.5% relative to the pure BT counterpart. Further experiments demonstrate that when this strategy is applied to the linear strontium titanate (ST) ceramic system, the breakdown strength of ST-4C ceramics increases from 23.04 kV/mm (for pure ST) to 33.67 kV/mm, while the dielectric constant (at 1 kHz) simultaneously grows from 410.4 to 528.5. In this work, an efficient and practical strategy is proposed for the synergistic enhancement of the dielectric constant and breakdown strength of ceramic dielectrics.