The Investigation of the Effect of La³⁺, Eu³⁺, and Sm³⁺ Ions on Photoluminescence and Piezoelectric Behavior of RE_1.90Y_0.10Zr₂O₇ (RE: Eu, Sm and Y: La, Sm, Eu) Pyrochlore‐Based Multifunctional Smart Advanced Materials

Abstract

A series of compounds with the general formula RE1.90Y0.10Zr2O7 (where RE includes Eu, Sm and Y includes La, Sm, Eu) were synthesized using a solid‐state reaction method. These compounds were analyzed through differential thermal analysis (DTA), thermogravimetric analysis (TG), X‐ray powder diffraction (XRD), and scanning electron microscopy (SEM). Additionally, their dielectric constant, loss tangent, piezoelectric charge constant, and Curie temperature were measured using an LCR meter, d33 meter, and TG/DTA. X‐ray diffraction results indicated that all samples crystallize in a cubic pyrochlore structure. Photoluminescence studies revealed that Eu3+ ions predominantly contribute to the emission, whether as activators or co‐activators. Among the phosphors, Eu1.90La0.10Zr2O7 exhibited a significantly longer afterglow compared to Sm1.90Eu0.10Zr2O7 and Eu1.90Sm0.10Zr2O7. Conversely, Sm1.90Eu0.10Zr2O7 demonstrated luminescence intensity that was 20 times greater than that of Eu1.90La0.10Zr2O7 and Eu1.90Sm0.10Zr2O7. Furthermore, all samples with characteristic Eu3+ emissions also exhibited piezoelectric properties. Curie temperature (Tc) of Eu1.90La0.10Zr2O7, Sm1.90Eu0.10Zr2O7, and Eu1.90Sm0.10Zr2O7 are 770°C, 830°C, and 845°C, respectively. Therefore, Sm3+ ion improves piezoelectric properties and Curie temperature when doping into the Eu2Zr2O7 host crystal.