Enhanced piezoelectricity and temperature stability in La-doped PIN-PMN-PT transparent ceramics by composition regulation

Transparent ferroelectric ceramics are popular due to their ability to couple optical and electrical properties. However, simultaneously achieving high electrical and optical performance in ceramics remains a formidable challenge. By using the two-step sintering process combined with a rare earth doping strategy, xLa-24PIN-42PMN-34PT transparent piezoelectric ceramics were prepared, achieving the coexistence of the highest known d33 (>1000 pC/N), excellent transmittance (T = 66.2% at 1600 nm), and the piezoelectric properties decrease by only 26.8% when approaching TC. PFM and in situ XRD results indicate that the parallel stripe-like and watermark-like coexisting ferroelectric domain structures, which are induced by La3+ doping, generate large piezoelectric responses. Light scattering loss is reduced by the small size of the ferroelectric domain structure. Excellent thermal stability is ensured by the tetragonal-dominated morphotropic phase structure. This work provides a valuable idea for the subsequent preparation of transparent ferroelectric ceramics with high performance.