UV and electron radiation-induced luminescence of Cu and Eu-doped lithium tetraborates (original) (raw)
Related papers
Photo-luminescence properties of Cu and Ag doped Li2B4O7 single crystals at low temperatures
Journal of Luminescence, 2012
UV excited photo luminescence from Li 2 B 4 O 7 :Cu and Li 2 B 4 O 7 :Cu, Ag single crystals has been investigated in the temperature range from 77 K to 300 K. An excitation band having a doublet structure at 240 nm and 262 nm was observed for the emission at 370 nm that corresponds to 1 A 1g-1 E g and 1 A 1g-1 T 2g crystal field components of the 3d 10-3d 9 4s 1 transition of Cu þ. The relative intensity of these components and their temperature dependence provide a measure of the off-center displacement of the Cu þ ground state in the crystal lattice site. The co-doped Ag plays a role of a sensitizer when doped with Cu and increases the overall emission as the emission between Ag states lies in the excitation region of Cu states. The 370 nm emission in both the crystals slightly decreases with temperature; however a sudden increase in the intensity around 264 K was observed.
Synthesis and thermoluminescence properties of rare earth oxides (Y, Ce-Lu) doped lithium triborate
Journal of Rare Earths, 2011
samples of undoped, terbium-doped (CdB 4 O 7 :Tb 3+), and manganese-doped (CdB 4 O 7 :Mn 2+) cadmium tetraborate have been prepared by solid-state reactions at 850°C. Using differential scanning calorimetry and X-ray diffraction, we have determined the melting point of CdB 4 O 7 (t m = 976°C) and shown that this compound melts incongruently. The observed monotonic decrease in the orthorhombic cell parameters of the doped materials indicates the formation of substitutional solid solutions (sp. gr. Pbca). The thermoluminescence intensity of the doped materials has been shown to depend on the nature and concentration of the activators and the irradiation time.
Growth and luminescent properties of Li 2 B 4 O 7 single crystal doped with Cu
Journal of Physics: Conference Series, 2009
The authors have primarily succeeded in the study of the technology for growing single crystal Li 2 B 4 O 7 doped with Cu ions by Bridgman technique. The TL-3D spectra show peaks at around 375 nm (3d 9 4s → 3d 10 radiative excitation transition). This success opened up an opportunity in the radiotherapy to manufacture scintillators for neutron detection. The kinetic parameters of thermal stimulation luminescence were investigated by the three point method.
Journal of Alloys and Compounds, 2011
Lithium tetraborate: Li 2 B 4 O 7 , (LTB) has been synthesized and doped with various Mn content by different methods, such as, high temperature solid state synthesis and solution assisted synthesis methods. Powder XRD results proved the formation of solid-solution by replacing Mn with Li ions in LTB lattice at lower amount of Mn doping, for example 0.1-3.0% Mn doping. In this research TL glow curves of Mn doped lithium tetraborate (LTB:Mn) produced by using different synthesis and doping methods and the effects of Ag, P and Mg as co-dopant were investigated. Structural and morphological analyses of products were done by using Fourier Transform Infrared spectroscopy (FTIR), Powder X-Ray Diffraction (XRD), Scanning Electron Microscopy (SEM), Transmission Electron Microscopy (TEM) and Raman Spectroscopy.
The effect of synthesis and doping procedures on thermoluminescent response of lithium tetraborate
Journal of Alloys and Compounds, 2011
Lithium tetraborate has been a scientific focus since 1960s by the courtesy of the thermoluminescence property it possesses. Moreover, it is utilized in surface acoustic wave apparatuses, in sensor sector and in laser technology owing to its non-linear optical characteristics. For the uses in thermoluminescence dosimetry lithium tetraborate is activated by addition of a variety of metals as dopants. This study includes the synthesis of lithium tetraborate by two methods (high temperature solid state synthesis and water/solution assisted synthesis), doping of activators into the matrix material synthesized and characterization of the products. Lithium tetraborate is readily commercially available in TL (Themoluminescence) dosimetry; hence, the main aim in this study was to specify the effect of synthesis and doping methods on the TL response. The heating temperature for the synthesis was 750 • C and the retention time as selected as 4 h for both methods. The synthesis stages were followed by doping step where the compounds of Cu, Ag and In in different proportions were doped in lithium tetraborate by solid state and solution assisted doping techniques. Characterization of the product was achieved by X-ray diffraction (XRD), Fourier transform Infra Red Spectroscopy (FT-IR) and Scanning Electron Microscopy (SEM) techniques. All samples prepared displayed TL response and the best TL signal was obtained from the sample produced by solid state synthesis and doped by solution assisted method with 0.1% Cu and 0.004% Ag.
Investigation of thermoluminescence properties of metal oxide doped lithium triborate
Journal of Materials Science, 2007
The luminescence properties of several doped materials are explored in many fields of application, including that of ionizing radiation dosimetry. These luminescence properties are essentially provided by the doping element. In this paper, we report TSL measurements of the trapping and recombination centers involved in the luminescence process of sol-gel derived glasses. Three doped species will be concerned: one transition metal (Cu), one rare-earth element (Ce) and a combination of both in the sol-gel silica matrix. By comparing the performances of these samples according to the criteria required for dosimetry by both TSL and OSL (sensitivity, dose-response, thermal fading), the results show that the simply doped samples really are potential candidates for fibered-OSL dosimetry.
MRS Proc., 2011
Photoemission spectroscopy using synchrotron radiation was used to determine the energy level structure of Mn doped 2 4 7 Li B O crystals. Photoemission studies provided evidence of Mn in the bulk crystal at 47.2 eV. Valence band analysis provided the presence of surface states but no acceptor sites. Cathodoluminescence studies were also made on undoped and Mn doped 2 4 7 Li B O using various beam energies from 5 to 10 KeV at room temperature. Self trapped exciton emission states are evident in the undoped and Mn doped Li 2 B 4 O 7 sample ranging in energies from 3.1 to 4.1 eV.
Optical Materials, 2014
Photoluminescence properties of Ce 3+ doped strontium haloborates synthesized by solution combustion technique were studied. Sr 2 B 5 O 9 Cl:Ce 3+ produce emission band peaking at 345 nm under 307 nm excitation radiation. Enhancement of luminescence intensity was observed when M + (Li + , Na + , K +) ions were used as co-dopant in Sr 2 B 5 O 9 Cl:Ce 3+. Charge compensation by Na + ion in Sr 2 B 5 O 9 Cl:Ce 3+ show strongest luminescence intensity at 345 nm under 307 nm excitation radiation.