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Calcium and barium zirconate powders based upon CaZrO 3:Eu3+ , A and BaZrO 3:Eu3+, A(A=Li+, Na+, K+) were prepared by combustion synthesis method and heating to ~1000 °C to improve crystallinity. The structure and morphology of materials were examined by X-ray diffraction (XRD) and scanning electron microscopy (SEM). XRD results showed that CaZrO 3:Eu3+, A and BaZrO 3:Eu3+, A (A=Li+, Na+, K+) perovskites possessed orthorhombic and cubic structures, respectively. The morphologies of all powders were very similar consisting of small, coagulated, cubical particles with narrow size distributions and smooth and regular surfaces. The characteristic luminescences of Eu 3 + ions in CaZrO 3 :Eu3+ , A (A=Li+, Na+, K+) lattices were present with strong emissions at 614 and 625 nm for 5D0 →7F2 transitions with other weaker emissions observed at 575, 592, 655, and 701 nm corresponding to 5D0 → 7Fn transitions (where n=0,1,3,4, respectively). In BaZrO3:Eu3 + both the 5D0 → 7F1and5D0 → 7F2 transitions at 595 and 613 nm were strong. Photoluminescence intensities of CaZrO3:Eu3+samples were higher than those of BaZrO 3:Eu3+lattices. This remarkable increase of photoluminescence intensity (corresponding to 5D0→7Fn transitions) was observed in CaZrO3:Eu3+and BaZrO3:Eu3+ if co-doped with Li + ions. An additional broad band composed of many peaks between 440 to 575 nm was observed in BaZrO3:Eu3+, A samples. The intensity of this band was greatest in Li + co-doped samples and lowest for K + doped samples.
Calcium and barium zirconate powders based upon CaZrO 3: Eu3 +, A and BaZrO 3: Eu3 +, A (A = Li +, Na +, K +) were prepared by combustion synthesis method and heating to ~ 1000 ° C to improve crystallinity. of materials were examined by X-ray diffraction (XRD) and scanning electron microscopy (SEM). XRD results showed that CaZrO 3: Eu3 +, A and BaZrO 3: Eu3 +, A (A = Li +, Na +, K +) perovskites possessed orthorhombic and cubic structures, respectively. The morphologies of all powders were very similar consisting of small, coagulated, cubical particles with narrow size distributions and smooth and regular surfaces. The characteristic luminescences of Eu 3 + ions in CaZrO 3: Eu3 +, A (A = Li + , Na +, K +) lattices were present with strong emissions at 614 and 625 nm for 5D0 → 7F2 transitions with other weaker emissions observed at 575, 592, 655, and 701 nm corresponding to 5D0 → 7Fn transitions (where n = 3,4, respectively). In BaZrO3: Eu3 + both the 5D0 → 7F1 and 5D0 → 7F2 t The remarkable increase of photoluminescence intensity (corresponding to 5D0 → 7Fn transitions) was observed in CaZrO3: Eu3 + lattices. The addition of BaZrO3: Eu3 + if co-doped with Li + ions. An additional broad band composed of many peaks between 440 and 575 nm was observed in BaZrO3: Eu3 +, A samples. The intensity of this band was greatest in Li + co-doped samples and lowest for K + doped samples.