Enhancing the performance of PMN-PT transparent piezoelectric ceramics by multi-rare earth doping based on the high-entropy strategy

Transparent piezoelectric ceramics, due to their ability to possess both piezoelectricity and light transmittance, have extensive applications in devices such as transparent sensors and transparent transducers. Generally, constructing ferroelectric domains with strong ferroelectricity and long-range order can yield a large piezoelectric coefficient. However, ferroelectric domain structures cause light scattering at the domain walls, thereby reducing the material's optical transmittance. Consequently, achieving both high optical transparency and a large piezoelectric performance simultaneously in piezoelectric ceramics presents a significant challenge. To address this challenge, La, Pr, Nd, Sm, Eu co-doped (1- x ) Pb(Mg 1/3 Nb 2/3 )O 3 - x PbTiO 3 (PMN-PT) transparent piezoelectric ceramics were prepared in this study based on a high-entropy strategy. Benefiting from the cocktail effect and lattice distortion effect of the high-entropy strategy, the largest piezoelectric performance d 33 of 1476 pC/N, along with a 60% linear transmittance and the highest linear transmittance up to 67% at 900 nm, along with high piezoelectric performance of 1334 pC/N were achieved. The influence of phase structure and ferroelectric domain structure on its optical, piezoelectric, dielectric, and ferroelectric properties was studied. The high-entropy transparent piezoelectric ceramics show enormous application potential in multifunctional photo-acoustic-electric coupling devices.