A novel lead-free relaxor with endotaxial nanostructures for capacitive energy storage

Dielectric capacitors with a fast charging/discharging rate,high power density,and long-term stability are essential components in modern electrical devices.However,miniaturizing and integrating capacitors face a persistent challenge in improving their energy density(W_(rec))to satisfy the specifications of advanced electronic systems and applications.In this work,leveraging phase-field simulations,we judiciously designed a novel lead-free relaxor ferroelectric material for enhanced energy storage performance,featuring flexible distributed weakly polar endotaxial nanostructures(ENs)embedded within a strongly polar fluctuation matrix.The matrix contributes to substantially enhanced polarization under an external electric field,and the randomly dispersed ENs effectively optimize breakdown phase proportion and provide a strong restoring force,which are advantageous in bolstering breakdown strength and minimizing hysteresis.Remarkably,this relaxor ferroelectric system incorporating ENs achieves an exceptionally high W_(rec)value of 10.3 J/cm^(3),accompanied by a large energy storage efficiency(η)of 85.4%.This work introduces a promising avenue for designing new relaxor materials capable of capacitive energy storage with exceptional performance characteristics.