Synthesis, spectral and surface investigation of novel CaMgB 2 O 5 :Dy 3+ nanophosphor for UV based white LEDs

Abstract This paper reports the surface, spectral and luminescent properties of Dy 3+ doped CaMgB 2 O 5 phosphor synthesized by combustion method. X-ray diffraction (XRD) was used to characterize the phase structure. X-ray photoelectron spectroscopy (XPS) was used to investigate the surface elemental composition and chemical states of the synthesized phosphor. The luminescent properties of CaMgB 2 O 5 :Dy 3+ phosphor was investigated by using photoluminescence emission, excitation and reflectance spectra. The excitation spectra under 576 nm emission consist of charge transfer band (CTB) and a series of 4f-4f transition states of Dy 3+ ion. The emission spectra of CaMgB 2 O 5 :Dy 3+ phosphor recorded at 349 nm excitation shows sharp peaks at 485 nm, 576 nm and 665 nm assigned to 4 F 9/2 → 6 H J/2 ( J = 15, 13, and 11) transitions of Dy 3+ ion. The CIE chromaticity color coordinates (0.38, 0.40) of CaMgB 2 O 5 : Dy 3+ phosphor falls in the yellowish white region of the horse shoe plot of color gamut. The band gap of the material was calculated to be 5 eV. The phosphor decay curve was also determined. The results show that CaMgB 2 O 5 :Dy 3+ phosphor might be potential phosphors for n-UV-based white light-emitting diodes.