Ion beam induced luminescence studies of sol gel derived Y2O3:Dy3+ nanophosphors

Abstract

a b s t r a c tPure and Dy 3 þ doped Y 2 O 3 are prepared by sol-gel technique. The samples are annealed at 900°C to obtain crystalline phase. X-ray diffraction (XRD) patterns confirm cubic phase of Y 2 O 3 . The crystallites size is calculated using Scherrer formula and is found to be in the order of 29.67 nm. The particles are found to be spherical in nature and their sizes are estimated to be 35 nm by scanning electron microscope (SEM) technique. Online ionoluminescence (IL) spectra of pure and Dy 3 þ doped Y 2 O 3 are recorded with 100 MeV Si 8 þ ions with fluence in the range 0.375-6.75 Â 10 13 ions cm À 2 . Undoped samples do not show IL emission for any of the fluence explored. Four prominent IL emissions with peaks at 488, 670, 767 nm and a prominent pair at 574 and 584 nm are observed in Dy 3 þ doped samples. These characteristic emissions are attributed to luminescence centers activated by Dy 3 þ ions due to 4 F 9/2 -6 H 15/2 , 4 F 9/2 -6 H 11/2, 4 F 9/2 -6 H 9/2 þ 6 H 11/2 and 4 F 9/2 -6 H 13/2 transitions respectively. Further, it is found that IL intensity at 574 nm decays rapidly with ion fluence. A broad and weak photoluminescence (PL) emission with peak at $ 485 nm and a strong emission at 573 nm are observed in ion irradiated Y 2 O 3 :Dy 3 þ . It is found that PL intensity increases with ion fluence up to 3 Â 10 10 ions cm À 2 and then it decreases with further increase of ion fluence. This may be attributed to lattice disorder produced by dense electronic excitation under swift heavy ion irradiation.

Photoluminescent and scintillant properties of highly transparent [(Y1‐xGdx)0.99Dy0.01]2O3 (x = 0 and 0.4) ceramics

“…Under 276 nm excitation of Gd 3+ for the 574 nm emission of Dy 3+ , however, the lifetime of x = 0.4 specimen climbs slightly to ~0.72 ms; this is primarily due to the energy transfer from Gd 3+ to Dy 3+ . The fluorescence lifetimes of the ceramic scintillators determined in this work are also in agreement with previously reported values of 0.41‐0.96 ms for Y 2 O 3 :Dy phosphor powders; which are much shorter than those for Y 2 O 3 :Eu and (Y,Gd) 2 O 3 :Eu ceramics (1.22‐2.66 ms) …”

“…Y 2 O 3 is well‐known as an excellent host material which accommodates several activation ions and is extensively applied in the fields of mercury‐free lamps, plasma display panels (PDP), field emission displays (FED), electroluminescent displays, and white LEDs . Among these activators, trivalent Dy 3+ ‐doped Y 2 O 3 phosphor powders show a hypersensitive emission in the yellow band at 574 nm (which corresponds to the 4 F 9/2 → 6 H 13/2 transition) as well as blue and red ones at 488 (the 4 F 9/2 → 6 H 15/2 transition) and 671 nm (the 4 F 9/2 → 6 H 11/2 transition), respectively .…”

Unraveling the Charge State of Oxygen Vacancies in Monoclinic ZrO2 and Spectroscopic Properties of ZrO2:Sm3+ Phosphor

“…This indicates that the color of the ZrO 2 :Sm 3+ phosphor changed slightly with fluence and that the color of the sample shifts toward green from yellow color. Without change of the chemical composition of the sample, the emission color is altered with fluence because of the change of symmetry and lattice distortion . The IL results of ZrO 2 :Sm 3+ , therefore, confirm that there are no impurities in the sample except for the Sm 3+ ions and that no energy transfer took place to the host under 100 MeV Si 7+ ion excitation.…”

“…IL measurement was carried out at room temperature under the excitation of 100 MeV swift Si 7+ ions. This IL setup was installed at the Material Science Beamline of 15 UD Tandem Accelerator, Inter University Accelerator Centre (IUAC), New Delhi, India . A pressure of 10 –6 torr was maintained inside the chamber during ion bombardment.…”

“…This IL setup was installed at the Material Science Beamline of 15 UD Tandem Accelerator, Inter University Accelerator Centre (IUAC), New Delhi, India. 48 A pressure of 10 −6 torr was maintained inside the chamber during ion bombardment. A focused ion beam with a diameter of ∼2 mm was used for excitation and the emission of light from the material was collected at an angle of 45°with respect to the incident ion beam using an Ocean Optics spectrometer (model HR4000).…”