LiCaBO3 :Dy(3+) /Eu(3+) phosphors were synthesized by a solid-state reaction. The synthesized materials were characterized using powder X-ray diffraction pattern (XRD) for confirmation. All the structural parameters were calculated from the XRD data. Scanning electron microscopy (SEM) images showed rod-like morphology. Photoluminescence (PL) emission spectra showed two emissions (484 and 577 nm) in Dy(3+) -doped LiCaBO3 :Dy(3+) phosphors with the concentration quenching effect and the critical distance was calculated to be about 22.76 Å. LiCaBO3 :Eu(3+) phosphor was effectively excited by a near-UV light of 392 nm. The emission spectra exhibited the transition from (5) D0 level to (7) FJ (J = 0-2) with main emission at 614 nm, which comes from the electrodipole transition because of the asymmetric point group. The quenching concentration of Eu(3+) is about 0.2 mol%, and the critical distance was calculated to be about 38.93 Å.

In this paper we report the modified solid state synthesis of Dy and Ce activated Sr6BP5O20, Ca6BP5O20 and (CaXSr(1−X))6BP5O20 phosphors. The prepared phosphors were characterized by the x-ray powder diffraction and photoluminescence techniques. The PL excitation spectra showed the excitation peaks ranging from 300 to 400 nm due to the 4f → 4f transitions of Dy3+ ions. This mercury-free excitation is useful for solid state lighting and light-emitting diode (LED). The PL emission spectrum of Dy3+ ion under 348 nm excitation was observed at 483 nm (blue) due to 4F9/2 → 6 H15/2 transitions. Other emissions were observed at 576 nm (yellow) due to 4F9/2 → 6H13/2 transitions and 670 nm (red) due to 4F9/2 → 6 H11/2 transitions in prepared borophosphate phosphor. Dy activated Ca6BP5O20 phosphor showed intense emission as compared with Sr6BP5O20 phosphors which have been reported in this paper. From these characteristics, Dy activated Sr6BP5O20, Ca6BP5O20 and (CaXSr(1−X))6BP5O20 phosphors are one of the candidates for the white LED. The PL emission spectra of Ce3+ ion in the Sr6BP5O20, Ca6BP5O20 and (CaXSr(1−X))6BP5O20 phosphors in the UV region under broad band excitation at around 247 nm are presented for the scintillation application.

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Modified solid state synthesis had been used to synthesize Zn4B6O13:Eu3+ phosphor. Compared to other methods, modified solid-state synthesis has several advantages.. Zn4B6O13:Eu3+ phosphor’s’ photoluminescence properties have been investigated.. The PL excitation spectra shows sharp peak at 393nm due to transition of 4f→5d. The shoulder peak of the PL emission spectra is observed at 614nm due to the 5Do→ 7F2 (red) transition of Eu3+ ion while the other peak is observed at 593nm due to the 5Do→ 7F1 (orange). All of the properties of the developed Zn4B6O13:Eu3+phosphor indicate that it could be beneficial in the lamp industry and solid state lighting.