Enhanced piezoelectricity, bright up-conversion and down-conversion photoluminescence in Er3+ doped 0.94(BiNa)0.5TiO3–0.06BaTiO3 multifunctional ceramics

Abstract

Multifunctional ceramics of 0.94(Bi1−xErxNa)0.5TiO3–0.06BaTiO3 have been fabricated by an ordinary sintering technique, and their structure, piezoelectricity, ferroelectricity and photoluminescence have been studied. The rhombohedral and tetragonal phases co-exist in the ceramics with x=0–0.036 and the concentration of Er3+ has no obvious influence on the crystal structure. The partial substitution of Er3+ for Bi3+ improves the piezoelectricity of the ceramic. The ceramics with x=0–0.02 possess strong ferroelectricity (Pr=26.7–29.6μC/cm2) and good piezoelectric properties (d33=146–181pC/N, kp=21.2–34.1%, respectively). After the addition of Er3+, the ceramics exhibit the characteristic up/down-conversion emission of Er3+ ions. The ceramic with x=0.032 possesses the strongest emissions at approximately 535nm and 549nm, which are attributed to 2H11/2→4I15/2 and 4S3/2→4I15/2 transitions, respectively. The ceramics with low Er2O3 levels exhibit simultaneously strong piezoelectricity, ferroelectricity and photoluminescence and thus may have a potential application in multifunctional devices.