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A Eu3+-doped CaCO3 phosphor with red emission was prepared by microwave synthesis. The scanning electron microscopy (SEM) image and laser particle size analysis show that the CaCO3:Eu3+ particles are needle-like in the length range of 5.0-10.0 μm. The results of X-ray diffraction (XRD) analysis, Fourier transform infrared spectroscopy (FT-IR), and Raman spectroscopy indicate that pure aragonite CaCO3:Eu3+ is prepared using microwave irradiation and the Eu3+ ion as a luminescence center inhabits the site of Ca2+. The photoluminescence excitation (PLE) spectrum shows that the strong broad band at around 270 nm and weak sharp lines in 300-550 nm are assigned to the charge transfer band of Eu3+-O2- and intra-configurational 4f-4f transitions of Eu3+, respectively. The photoluminescence (PL) spectrum implies that the red luminescence can be attributed to the transitions from the 5D0 excited level to the 7FJ (J = 0, 1, 2, 3, 4) levels of Eu3+ ions with the mainly electric dipole transition 5D0 → 7F2 (614 and 620 nm), and the Eu3+ ions prefer to occupy the low symmetric site in the crystal lattice.
The Eu3 + -doped CaCO3 phosphor with red emission was prepared by microwave synthesis. The scanning electron microscopy (SEM) image and laser particle size analysis show that the CaCO3: Eu3 + particles are needle-like in the length range of 5.0-10.0 μm. The results of X-ray diffraction (XRD) analysis, Fourier transform infrared spectroscopy (FT-IR), and Raman spectroscopy indicate that pure aragonite CaCO3: Eu3 + is prepared using microwave irradiation and the Eu3 + ion as a luminescence center inhabits the site of Ca2 +. The photoluminescence excitation (PLE) spectrum shows that the strong broad band at around 270 nm and weak sharp lines in 300-550 nm are assigned to the charge transfer band of Eu3 + -O2- and intra-configurational 4f-4f transitions of Eu3 + . The photoluminescence (PL) spectrum implies that the red luminescence can be attributed to the transitions from the 5D0 excited level to the 7FJ (J = 0, 1, 2, 3, 4) levels of Eu3 + ions with the mainly electric dipole transition 5D0 → 7F2 (614 and 620 nm), and the Eu3 + ions prefer to occupy the low symmetric site in the crystal lattice.