Preparation and tunable luminescence of CaCO3: Eu3+, Tb3+ phosphors

Luminescent tunable phosphors CaCO3: Eu3+, Tb3+ 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 Tb3+ and Eu3+ ions were uniformly introduced into the host lattice of CaCO3 entering substitutionally in Ca2+ 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 5D4→7FJ (J=3-6) for Tb3+ and 5D0→7FJ (J=0-3) for Eu3+ were observed, and the luminescent intensities and emitting colors of Eu3+-Tb3+ co-doped CaCO3 phosphors could be gradually changed between red and green by changing the Eu/Tb atomic ratio and the excitation wavelength.