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Luminescent tunable phosphors CaCO 3 : Eu 3+ , Tb 3+ were synthesized by a microwave co-precipitation method. The structure and micro-morphology of samples were characterized and analyzed by an X-ray powder diffraction (XRD) and a scanning electronic microscope (SEM), results showed that Tb 3+ and Eu 3+ ions were uniformly introduced into the host lattice of CaCO 3 entering substitutionally in Ca 2+ sites. The photoluminescence (PL) properties were characterized by PL, PL excitation spectroscopy and chromaticity coordinates. Under the excitation at 235 nm and 267 nm, the transitions of 5 D 4 → 7 F J ( J =3–6) for Tb 3+ and 5 D 0 → 7 F J ( J =0–3) for Eu 3+ were observed, and the luminescent intensities and emitting colors of Eu 3+ –Tb 3+ co-doped CaCO 3 phosphors could be gradually changed between red and green by changing the Eu/Tb atomic ratio and the excitation wavelength. |
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