Optical properties of rare earth-activated Ca3(PO4)2:RE (RE = Eu3+ and Dy3+) phosphors prepared by wet chemical synthesis

Optical properties of rare earth-activated Ca3(PO4)2:RE (RE = Eu3+ and Dy3+) phosphors obtained by wet chemical synthesis method, are reported in this paper. The phase confirmation of synthesized phosphor host is done by X-ray diffraction study. SEM images of the sample host reveal irregular morphology with collection of particles and porous nature. The crystal structure is not viewed with naked eyes, although particle size ranges from 2–5 micrometres. Photoluminescence characterization of Ca3(PO4)2:Eu3+ gives characteristic orange–red emission at wavelengths of 594, 613 and 617 nm upon near UV excitation at 397 nm attributed to 5D0 → 7F1, 7F2 transition of rare earth Eu3+ ion. Whereas Ca3(PO4)2:Dy3+ gives blue–yellow emissions at wavelengths 483 and 574 nm due to near UV excitation at wavelength of 351 nm, which are corresponding to 4F9/2 → 6H15/2, 6H13/2 transitions of dopant ion Dy3+. Colour coordinates from CIE diagram of 483 and 574 nm are obtained at (x = 0.0781, y = 0.1704) and (x = 0.471, y = 0.527) for the Ca3(PO4)2:Dy3+ phosphor. Whereas in the case of Ca3(PO4)2:Eu3+ for an emission wavelength of 613 nm, the colour coordinates are found to be (x = 0.674, y = 0.325). The presented optical investigation of phosphor displays that the reported phosphor can be a potential contender for ecofriendly solid-state lighting.