Structural and spectral studies of highly pure red-emitting Ca3B2O6:Eu3+ phosphors for white light emitting diodes

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• Ca 3 B 2 O 6 :Eu 3+ phosphors were investigated as an alternative for red light. • Highly pure red emission was realized upon near UV excitation. • The phosphor has high color purity ~ 90%. Near UV excited highly pure red light emitting Ca 3 B 2 O 6 :Eu 3+ phosphor was synthesized via a solution combustion method. The prepared samples were examined using Powder X-ray diffraction (XRD), Fourier transform infrared (FT-IR), X-ray photoelectron spectroscopy (XPS) and Photoluminescence (PL) spectroscopy for their structural, spectral, surface, and luminescent studies. The XRD and FTIR results showed the formation of a single phase Ca 3 B 2 O 6 compound with BO 3 and BO 4 structural units. PL emission spectra under near UV excitation show characteristic emission for the Eu 3+ ion ( 5 D 0 → 7 F j , j = 0, 1, 2, 3 and 4) with the main red emission peak at 614 nm corresponding to the 5 D 0 → 7 F 2 transition state of the Eu 3+ ion. The XPS results depicted that all the elements were presented on the surface of the material and the Eu ion was presented in the (+3) state. The density of states and bandgap of the material was approximated by employing the density functional theory. Moreover, the decay time, International Commission on Illumination coordinates, and color purity were also calculated. Phosphor with short decay time, CIE coordinates corresponds to strong red emission and high color purity reveal that the phosphor can be a potential material as a red component for white light emitting diodes (wLED).