Photoluminescence and thermoluminescence studies of 100 MeV Si8+ ion irradiated Y2O3:Dy3+nanophosphor

This paper reports on swift heavy ion (SHI) induced defects that were correlated to the color tuning in Dy3+ activated Y2O3 nanocrystals for possible application in white light emitting diodes and high energy dosimetry. The optimum concentration of trivalent dysprosium (Dy3+) doped with yttrium oxide (Y2O3) was prepared by the solution combustion technique. X-ray diffraction results revealed that the obtained powder material is a single phase body center cubic structure. The transmission electron microscopy images revealed that the particles were irregular shape with an average size of 37 nm. The composition of the synthesized materials were confirmed by Fourier transformed infra-red transmittance and Raman spectroscopy. The Dy(3+ )doped Y2O3 upon illumination with ultraviolet light showed the characteristic greenish yellow emission of Dy3+. This greenish yellow emission was enhanced when it was exposed to 100 MeV swift Si8+ ions and the ratio between yellow and blue emission could be tuned. This is ascribed to the SHI induced electrons/holes traps and the energy transfer between the electron/hole recombination centers and activator states in the host. The life time enhancement was found to be 931.55 mu s and the photometric characterization showed that SHI influences the phosphor material to achieve pure white emission for light emitting diode applications at and beyond a fluence of 1 x 10(11) ions cm(-2). Thermoluminescence (FL) glow curves of 100 MeV Si8+ ion irradiated samples showed three glows with peaks at 408, 467 and 592 K. The prominent peak (408 K) intensity increased upto a fluence of of 1 x 10(11) ions cm(-2). TL trapping parameters were calculated using glow curve deconvolution (GCD) technique and the obtained results are discussed in detail.