TY  - JOUR
AU  - Zhang, Amei
AU  - Man, Wanchang
AU  - Jing, Ruiyi
AU  - Hou, Hongping
AU  - Yang, Yule
AU  - Zhang, Leiyang
AU  - Du, Hongliang
AU  - Jin, Li
PY  - 2026
TI  - Aliovalent co-doping induces relaxor states with enhanced electrostrain in BNT-based ceramics
JO  - Journal of Materiomics
SN  - 2352-8478
VL  - 12
IS  - 1
AB  - Developing high-performance lead-free electrostrain materials is key to advancing next-generation electromechanical technologies. Here we report an aliovalent co-doping strategy in (Bi0.5Na0.5)TiO3-based (BNT-based) ceramics, where simultaneous A-site (Li+) and B-site (Nb5+) co-doping yields (1−x)Bi0.5(Na0.81K0.19)0.5TiO3-xLiNbO3 (BNKT-xLN, x= 0.01–0.04) compositions. The aliovalent substitution disrupts long-range ferroelectric order, enhances lattice distortion, and promotes a relaxor-like state with diffuse phase transitions and strong dielectric dispersion. Complementary polarization–electric field (P–E) and strain–electric field (S–E) measurements demonstrate a progressive evolution from classical ferroelectrisc to nonergodic relaxor behavior as the doping level increases. The optimized composition at x = 0.02 exhibits a large reversible electrostrain of approximately 0.55% associated with a temperature-driven reversible phase transition. Notably, BNKT-xLN ceramics achieve electric-field-induced polarizations exceeding 50 μC/cm2, while exhibiting a relatively low electrostrictive coefficient Q33 of ~0.018 m4/C2, suggesting their potential as energy storage matrices due to the weak polarization–strain coupling effect. These results underscore the importance of aliovalent co-doping strategy in modulating the energy landscape of BNT-based systems, offering a viable strategy for developing high-strain, lead-free electroceramics suited to next-generation actuators and energy storage devices.
UR  - https://doi.org/10.1016/j.jmat.2025.101107
DO  - 10.1016/j.jmat.2025.101107