Ag nanoparticle effects on the thermoluminescent properties of monoclinic ZrO(2) exposed to ultraviolet and gamma radiation.

The goal of this work was to analyse ZrO(2) in the pure state and when doped with Ag nanoparticles, by electron microscopy, x-ray diffraction and thermoluminescence methods. According to the results obtained, Ag nanoparticles did not modify the morphology or the crystalline structure of the ZrO(2). The thermoluminescent (TL) response of pure ZrO(2) showed two peaks, one at 334 K and the other at 417 K, when it was exposed to ultraviolet (UV) radiation, and at 342 and 397 K when gamma radiation was used. For ZrO(2) impregnated with Ag nanoparticles a diminished TL intensity due to nanoparticle shielding was observed, but the glow curve shape was similar. However, when Ag nanoparticles were added during the ZrO(2) synthesis, a shift of the TL peaks towards higher temperature values with reference to pure ZrO(2) was observed. A linear dependence of the integrated TL signal as a function of the irradiation dose was observed in all analysed samples. It was possible to determine some kinetic parameters, such as activation energy, kinetic order and frequency factor, using the sequential quadratic programming glow curve deconvolution; it was found that these values are highly dependent on the type of radiation used. Ag nanoparticles present in ZrO(2) also modified the kinetic parameters, mainly when they were added during the synthesis of ZrO(2). Our results reinforce the possibilities of using pure and doped ZrO(2) as an appropriate dosimetric material in radiation physics.