Study on the Effect of γ-Irradiation on Gadolinium Oxysulfide Nanophosphors (Gd₂O₂S-NPs)

Abstract

Gadolinium oxysulfide nanophosphors (Gd 2 O 2 S-NPs) have been successfully synthesized using -irradiation and hydrogenation treatment. The primary stage of Gd 2 O 2 S-NPs synthesis was carried out using various doses of -irradiation to form diverse sizes of Gd 2 (SO 4 ) 3 precursor, followed by hydrogenation treatment at 900 ∘ C for 2 hours to form Gd 2 O 2 S-NPs. Then, the nanophosphors were characterized for the structure, morphology, and luminescence properties through X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM), and photoluminescence spectrometer (PL). Pure hexagonal phase of Gd 2 O 2 S-NPs was obtained with high crystallinity and without any impurities. The morphologies were observed from grain-like nanostructures transformed to spherical shape as the irradiation dose reached 40 kGy. Besides, Gd 2 O 2 S-NPs which were prepared at highest irradiation dose of 40 kGy show highest intensity of emission peak at 548 nm and corresponded to Stark level transition from the 6 G J state of Gd 3+ ion. It can be emphasized that the different doses of -irradiation influenced the nucleation event of Gd 2 (SO 4 ) 3 precursor thus affecting the morphology and size particles of Gd 2 O 2 S-NPs. Hence, from the results, it can be suggested that Gd 2 O 2 SNPs can be a promising host for optical applications.

Gd2O2S:Eu3+ Nanophosphors: Microwave Synthesis and X-ray Imaging Detector Application

“…PVP covered the precursor surface and formed a protective layer, controlling the growth rate of the precursor particles 30 . Since the PVP concentration was high enough to be adsorbed on the surface of the particles in all the directions to entail an isotropic growth, stable spherical nanophosphors were obtained 20 . Figure 4a shows the photoluminescence spectra of the samples obtained under the excitation at 325 nm.…”

“…The effect of synthetic strategy such as microwave irradiation power and calcination temperature on the size, crystallity and luminescence properties has been compared. 3 and (NH 4 ) 2 SO 4 were weighed in a suitable stoichiometric ratio and were dissolved in a 1:1 mixture of deionized water and ethylene glycol 20 . 2% w/v of PVP was added to the reaction mixture and vigorous stirred for 2 h. The resulting mixture was then divided into four samples (control, 167, 500, and 1000 W) and microwave irradiated for 2 min.…”

Synthesis, characterization and formation mechanism of Gd2O2S:Pr3+,Ce3+ phosphors by sealed triple-crucible method

“…Lanthanide-doped luminescent materials have received considerable attention for their wide applications in high-resolution displays, integrated optical systems, memory devices, photonics, optoelectronics, afterglow, solid state lasers and especially biological label phosphors [1][2][3]. Moreover, Gd 2 O 2 S is an excellent luminescent host material, which has been deliberated as a host for optical activation with various numbers of rare-earth ions to reveal different luminescence peaks of the activators [4]. Among them, the Gd 2 O 2 S:Pr 3+ ,Ce 3+ phosphors have attracted much attention for their high density (7.34 g.cm −3 ), high chemical and thermal stability as well as wide band gap energy in the range of 4.6 to 4.8 eV [5,6].…”

Physical and optical studies of Gd2O2S:Eu3+ nanophosphors by microwave irradiation and γ‐irradiation methods

“…Phosphor materials are unique materials that exhibit luminescence properties after absorbing a certain level of energy . Gadolinium oxysulfide (Gd 2 O 2 S) is a well known phosphor material based on its wide band‐gap energy (4.6–4.8 eV), making it favourable for use as a matrix for acquiring luminescent emitting materials . It also has high density (7.34 g·cm −3 ) and refractive index ( n = 2.1–2.3), permitting high light absorption and high energy transfer efficiency for luminescent materials .…”