Synthesis and luminescent properties of a white light phosphor KBa₂Nb₅O₁₅:Na⁺, Dy³⁺ for light-emitting-devices

Graphical abstract: - Highlights: • A novel red phosphor KBa₂Nb₅O₁₅:Dy³⁺ was synthesized and investigated firstly. • Crystal structure and characteristic luminescence properties are discussed. • The charge compensation mechanism is also investigated. • It has low color tolerance and better CIE chromaticity coordinates. - Abstract: The white light emission phosphor KBa₂Nb₅O₁₅:Dy³⁺ was synthesized by solid-state method. X-ray diffraction (XRD) study reveals that all the Dy³⁺ doped phosphors are single phase. Strong excitation peaks of KBa₂Nb₅O₁₅:Dy³⁺ were found around 380–400 nm, matched well with the NUV LED chip. Under 388 nm excitation, the phosphor exhibited intense white emission by combining the two emission peaks at 477 nm and 572 nm, attributed to the characteristic ⁴F_9/2–⁶H_15/2 and ⁴F_9/2–⁶H_13/2 transition of Dy³⁺. The optimum doping concentration of Dy³⁺ is found to be 3%, whose Commission International de l’ Eclairage (CIE) chromaticity coordinates and correlated color temperature are (0.395, 0.422) and 3925 K, respectively. The results indicate that the KBa₂Nb₅O₁₅:Dy³⁺ phosphor could be considered as a potential candidate for white-LEDs