Effect of swift heavy ion irradiation on structural, optical and luminescence properties of SrAl2O4:Eu2+, Dy3+ nanophosphor

Abstract

Abstract The effect of energy deposition by swift heavy ion (SHI) irradiation on the structural, optical and luminescence properties of the SrAl 2 O 4 :Eu 2+ , Dy 3+ nanophosphor synthesized by a combustion method has been presented. The samples were irradiated with 120 MeV Ag 9+ SHIs at fluences in the range of 1×10 12 ions cm −2 to 1×10 13 ions cm −2 . The X-ray diffraction results revealed that the obtained powder corresponds to the monoclinic-phase with space group P2 1 and the results also indicate that the SHI irradiation did not cause any change in the crystal structure of the phosphor. However, a decrease in the crystallinity was observed. Under 330 nm excitation, the PL emission spectra show a broad band centered at 516 nm which corresponds to the 4f 6 5d→4f 7 ( 8 S 7/2 ) transition of the Eu 2+ ion. The PL intensity of the phosphors was found to decrease with an increase in the ion fluences, which may be due to the enhancement in the non-radiative recombination via additional deep level traps introduced by the SHI irradiation. SHI irradiation enhanced the phosphorescence life time of the phosphors. After SHI irradiation, a blue shift in the diffuse reflectance spectra was observed. The thermoluminescent (TL) glow curve of the SHI irradiated phosphors showed a broadband with a shift in the peak position from 375 K to 391 K with an increase in the ion fluence. Also, the TL intensity has increased with an increase in the ion fluences.