Structural and Photoluminescence Properties of White Emitting Phosphor Based on (Ce0.98Dy0.02)MgAl11O19 Magnetoplumbite Structure

A series of white emitting phosphors based Ce_1–xDy_xMgAl₁₁O₁₉ (x = 0.01–0.05) were synthesized by solid state chemistry. The systematic studies of the luminescent properties of these phosphors were performed. It is established that the (Ce_0.92Dy_0.02)MgAl₁₁O₁₉ (CMAD) is crystallizes in hexagonal crystal sys-tem with P63/mmc (194) space group and its unit cell parameters are a = 5.4037 Å, b = 5.4037 Å, c = 21.9296 Å; α = 90.00°, β = 90.00°, γ = 120.00°; Z = 2; V = 587.41 (Å)³. SEM technique was used elucidate the surface morphology and particle sizes of CMAD. The excitation spectra reveal that the UV-Vis light efficiently excite Ce_1–xDy_xMgAl₁₁O₁₉ in the range 220–400 nm. The emission spectrum of (Ce_0.98Dy_0.02)MgAl₁₁O₁₉ shows two strong peaks at 474 and 570 nm as well as weak bands at 657, 696, and 750 nm. The luminescence decay time (τ) was calculated and found 1.22 ms.