• • The FksS metastructure achieved a d33 of 194 pC/N, a 24% enhancement over conventional solid BaTiO3, demonstrating that geometric design can surpass intrinsic material limits.
• • High d33 requires simultaneous high polarization charge conversion efficiency and low compression modulus (stiffness); SR structures showed optimal charge conversion, while FksS exhibited low stiffness.
• • The FksS structure displayed isotropic and stress-insensitive mechanical properties, making it suitable for varying loading conditions and enhancing structural reliability.
• • 3D printing enables fabrication of complex metastructures (SR, Octa, TPMS, hybrid) that are otherwise impossible with conventional ceramic processing, opening new design自由度 for piezoelectric devices.