(686c) Thermoluminescent Dosimetric Analysis of Ag and Cu Doped LiB3O5

Production

Synthesis of Ag and Cu doped LiB₃O₅ crystals was carried out by precipitation, using water as a solvent. Impure crystals were produced at a synthesis temperature of 70 ^oC. A 5g of Ag and Cu doped LiB₃O₅ precipitate was obtained upon evaporation of water in the solution. The precipitates were calcined at a temperature of 750 ^oC for one hour. The calcined materials were grounded finely and subjected to severalcharacterizations.

Characterization

SEM analyses were performed for the doped and undoped samples of LiB₃O₅. The XRD properties of the samples were obtained. The UV-Vis absorbance spectra of the samples were obtained at room temperature. Spectra were recorded between 200 and 1200 nm. The photoluminescence (PL) measurements were carried out. The glow curves of the samples has been obtained using TLD reader.

Results

The XRD patterns obtained for the samples showedthat production of LiB₃O₅ with orthorhombic structure was successful since allof the main peaks of LiB₃O₅ coincide with the JCPDS data. It was seen that the dopant added did not interfere withthe crystal structure. As it can easily be detected addition of the dopants didnot have any significant effect on the crystal structure of LiB₃O₅ produced.

SEM was carried out to check the morphologies of the samples.According to the SEM images, the samples produced by the co-precipitation method shows the agglomerated surface.

The UV-Vis absorption spectra for the samples showed that the maximum absorbance was observed at 250nm. The result showed that a clear monotonic and increasing dependence of the intensity of the absorbance as a function of dopants.

The dosimetric properties of LiB₃O₅ doped with Ag and Cu were determined by using HarshawTLD Reader Model 3500. The heating rate was chosen as 10^oC/s was usedfrom 50 to 350^oC. The examined dosimeters were exposed to X-rays at room temperature. The sample amount was 0.5g. The samples have shown the TL response. The pattern of the glow curves changed with the change of dopants.

Conclusions

The TL response of LiB₃O₅ has been compared with the commercial TLD100. The observation concludes that the doped LiB₃O₅ has the TL behavior. The glow curves of the LiB₃O₅ shows different shape with the change of dopants.