White light emitting thermally stable bismuth phosphate phosphor Ca3Bi(PO4)3:Dy3+ for solid-state lighting applications

White light emitting dysprosium-doped Ca₃Bi(PO₄)₃ phosphor was successfully synthesized via co-precipitation method for the first time and the structural, vibrational, morphological, and luminescent properties have been investigated for solid-state lighting applications. X-ray diffraction (XRD) and structural refinement studies reveal that the synthesized phosphors consist of single phase with cubic structure. The field emission scanning electron microscopy (FE-SEM) images reveal that the as-synthesized phosphor has micron size particle with an irregular shape. Under near-ultraviolet (n-UV) and blue excitation, the phosphor exhibits white light emission via a combination of blue (~484 nm) and yellow (~575 nm) emission bands. The optimized concentration of Dy³⁺ ions is 6.0 mol % after which the concentration quenching takes place. The process of energy transfer between Dy³⁺ ions is due to dipole-dipole interaction, which was confirmed by applying Dexter's theory. The CIE chromaticity coordinates for the optimized phosphor were (0.329, 0.377), and they lie in the white light region. The emission intensity remains to be 83.41% at 373 K to that of at room temperature, which indicates good thermal stability. The above mentioned results demonstrate that Ca₃Bi(PO₄)₃ is a potential phosphor for solid-state lighting applications.