Optical characterization of YAl3(BO3)4:Dy3+–Tm3+ phosphors under near UV excitation

Abstract Dy 3+ and Tm 3+ co-doped YAl 3 (BO 3 ) 4 (YAB) phosphors were prepared by solid-state reaction method at 1200 °C/3 h. The average crystallite size was determined as 52.09 nm from the X-ray diffraction measurements. Upon 352 and 359 nm near ultra violet excitation, the YAB:Dy 3+ –Tm 3+ phosphors exhibit Dy 3+ : 4 F 9/2  →  6 H J ( J  = 15/2, 13/2, 11/2) and Tm 3+ : 1 D 2  →  3 F 4 transitions with different luminescence intensity. The photoluminescence emission and decay measurements revealed the energy transfer from Dy 3+ to Tm 3+ ions under 359 nm excitation only. The energy transfer between Dy 3+ and Tm 3+ takes place in Dy 3+ –Tm 3+ clusters through exchange interaction mechanism. The Commission International de I’Eclairage chromaticity coordinates of YAB:Tm 3+ phosphor ( λ ex  = 359 nm) were found very close to the European Broadcasting Union and National Television Standard Committee illuminants. The emission color of the studied phosphors could be tuned from blue-to-white as a function of excitation wavelength. The YAB:Dy 3+ –Tm 3+ phosphors can be used as potential candidates in display technology.