화학공학소재연구정보센터
Materials Research Bulletin, Vol.91, 140-147, 2017
Synthesis, spectral and surface investigation of novel CaMgB2O5:Dy3+ nanophosphor for UV based white LEDs
This paper reports the surface, spectral and luminescent properties of Dy3+ doped CaMgB2O5 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 CaMgB2O5: 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 Dy3+ ion. The emission spectra of CaMgB2O5:Dy3+ phosphor recorded at 349 nm excitation shows sharp peaks at 485 nm, 576 nm and 665 nm assigned to F-4(9/2) -> H-6(1/2) (I= 15, 13, and 11) transitions of ion. The CIE chromaticity color coordinates (0.38, 0.40) of CaMgB2O5: Dy3+ phosphorDy(3+) 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 CaMgB2O5: Dy3+ phosphor might be potential phosphors for n-UV-based white light-emitting diodes. (C) 2017 Elsevier Ltd. All rights reserved.