Contaction of Atoms for Outstanding Dielectric Characteristics in Kx-Passivated Polymer Dielectrics

High dielectric characteristics polymer dielectrics are crucial for high-power, high-integration, and high-energy storage density electrical devices and film capacitors. However, polymer dielectrics accumulate much charge during operation, causing local electric field distortion and flashover or breakdown. The deep-level defect state (electron/hole accumulation center) is a fundamental factor affecting dielectric strength. Unfortunately, related research, especially on passivating deep-level defects in polymer dielectrics, is minimal. In this paper, based on experiments and first-principles calculations, it is found that KX (X=F, Cl, Br, I) effectively passivates deep-level defect states in polymer dielectrics. Further analysis of the physical passivation mechanism reveals that the deep-level defect cation passivation principle is the cation dipole effect on polymers. The principle of anion passivation of deep-level defects by suspending anions and cations is the key to producing more stable C covalent bonds. This stable covalent bond transfers the local charge from the C with the lone electron pair that originally contains the hanging bond. Therefore, some transfer occurs and the anion implements effective passivation. This paper addresses the design of high-performance polymer dielectrics, providing a reference for experimental and theoretical analyses.