Field-Gradient-Driven Molecular Polarization and Trap-State Modulation in Cross-Linked Polyethylene Dielectrics

Electrical failure of cross-linked polyethylene (XLPE) insulation originates from microdefects with strongly intensified local fields. Here we establish a dielectrophoresis–guided molecular targeting strategy that directs anthraquinone (AQ) toward these high-field regions. The field-gradient–driven migration of AQ leads to localized deep-trap formation, efficient carrier capture, and suppression of field distortion. At an optimal 1 wt % loading, AQ enhances the direct current breakdown strength of XLPE by 44%, reduces conductivity, and regulates trap states, while maintaining processability. These results reveal a coupled mechanism of field-driven molecular redistribution and trap-state regulation, providing new insight into the dynamic charge–field interactions that govern electrical reliability in polymer dielectrics, and establishing a generalizable mechanism for defect-level stabilization via dielectrophoretic targeting.