Effect of acceptor–donor co‐doping on the microstructure and electrical properties of BiScO 3 –PbTiO 3 ‐based ceramics

Abstract Designing BiScO 3 ‐PbTiO 3 (BS–PT) ceramics that merge high Curie temperature ( T C ) and large piezoelectric coefficient ( d 33 ) has always been a significant challenge for high‐temperature applications. Doping is a commonly used and effective method for enhancing the electrical performances of piezoelectric ceramics. In this study, the Li + /W 6+ acceptor–donor co‐doping method was used to enhance the piezoelectric properties of 0.36BiSc 1‐ x Li x O 3 –0.64PbTi 1‐ y W y O 3 (0.36 x = 0.64 y ) ceramics. The optimal electrical performance was observed at x = 0.01 near morphotropic phase boundaries, with a large d 33 (505 pC/N), high T C (407°C), huge remnant polarization ( P r ∼ 40.9 μC/cm 2 ), and inverse piezoelectric coefficient ( d 33 * = 601 pm/V). Rietveld refinement and piezoelectric force microscopy results revealed that incorporating Li + /W 6+ into the BS–PT ceramics decreased the T phase proportion and domain size and increased the domain wall density. The enhancement in piezoelectricity can be attributed to the lowered energy barrier resulting from the reduced T‐phase proportion and complex domain structure, which promotes polarization rotation and facilitates domain wall motion. This work demonstrates that acceptor–donor co‐doping is a promising strategy for optimizing the electrical performance of the BS–PT ceramics.