Wydział Chemii

Karolina Fiączyk

Andrzej J. Wojtowicz

Winicjusz Drozdowski

Kamil Brylew

Eugeniusz Zych

2016

Radiation Measurements

90

140-144

10.1016/j.radmeas.2016.01.006

Naukowa

Angielski

Artykuł

Radio- and thermoluminescent properties of HfO₂:Ti sintered ceramics were investigated in the temperature range of 10-300K. Fabrication atmosphere altered somewhat the efficiency of radioluminescence but did not affect the spectral distribution of the broad scintillation band covering the 380-570nm range of wavelengths and peaking at 522nm at 10K and about 490nm at 300K. The analogous shift was seen in photoluminescence. Scintillation efficiency was continuously growing from 10K to 300K, while photoluminescence intensity was stable in the 10-250K range of temperatures and was reduced by about 30% at 300K. Analysis of these observations allowed to conclude that diffusion of carriers generated upon the impact of high-energy photons towards the Ti emitting center is strongly temperature-dependent and inferior at lower temperatures. Upon exposure to X-rays at 10K the ceramics stored more than 50% of the absorbed energy. This energy could be recovered later upon thermal stimulation of the ceramics. Four main thermoluminescent peaks were then produced at 95, 140, 243 and 278K. This effect was tentatively associated with theoretically predicted self-trapping of holes in HfO₂. The so-called partial cleaning and T_max-T_stop experiments indicated that some fraction of traps shows a continuous distribution of their depths.

Radioluminescence, photoluminescence, thermoluminescence, Hafnia

http://dx.doi.org/10.1016/j.radmeas.2016.01.006