Photoluminescence and piezoelectric behaviour of Y2Zr2O7 pyrochlore-based multifunctional materials and the influence of Eu3+ and Sm3+

Y2Zr2O7-doped with Eu3+ and Sm3+ phosphors were prepared for the first time as multifunctional smart materials using a solid-state reaction method at 1400(o)C. Thermal behaviour, crystal structure, surface morphology, and elemental analysis were characterized using thermogravimetric (TG) and differential thermal (DTA) analyses, X-ray diffraction (XRD) and scanning electron microscope equipped with energy-dispersive X-ray spectroscopy (SEM-EDX). Experimental results revealed that both phosphors have a pyrochlore structure with a cubic crystal system. Photoluminescence properties were also measured and red emission was observed from Y1.90Eu0.10Zr2O7 and Y1.90Sm0.10Zr2O7 phosphors. Dielectric constant, loss tangent, piezoelectric charge constant, and Curie temperature of all the samples were determined using an LCR-meter, d(33)-meter, and TG/DTA. Eu doping in Y2Zr2O7 resulted in a high dielectric constant (9.61) and low loss tangent (1.67%) values, whereas high piezoelectric charge constant (0.68 pC/N) and high Curie temperature (820 degrees C) could be obtained using Sm-doped Y2Zr2O7.