Strain-Adaptive Dielectric Metamaterials via Bioinspired “Ligament-Bone” Architecture for Ultrahigh-Energy Capacitive Storage

Polymer dielectrics for capacitive energy storage face fundamental trade-offs between breakdown strength, energy density, efficiency, and mechanical robustness. Herein, we break this paradigm by designing a bioinspired strain-adaptive dielectric metamaterial with a multiscale “ligament-bone” architecture. The “ligament” phase epoxy-functionalized polyvinylidene fluoride-based polymer provides dynamic constraints to suppress ferroelectric loss, while the “bone” units, alumina-coated barium titanate nanocores (Al 2 O 3 @BaTiO 3 ), engineered with a strain-responsive “periosteum” shell, mitigate interfacial distortion and carrier migration. This hierarchical design synergistically enables unprecedented electro-mechanical properties: a record-high energy density of 26.1 J cm −3 with 90.2% efficiency at 600 MV m −1 , coupled with a Young's modulus of 2.13 GPa. Operando characterizations and multiscale simulations reveal that strain-adaptive reconfiguration of polymer chains and core-shell interfaces dynamically optimizes field/charge distribution under extreme conditions. This biomimetic strategy establishes a universal framework for designing next-generation dielectrics for extreme-condition electronics.