Degradation effects in TlBr single crystals under prolonged bias voltage

Electrical properties of TlBr purified by hydrothermal annealing in pure water were studied by I–V, capacitance and photocurrent measurements using Ti-electrodes which were deposited by electron-beam evaporation. Time characteristics of the current during the aging were recorded under fixed voltage (0–200 V) at different temperatures 277–353 K. The samples were additionally characterised by the X-ray powder diffraction and rocking curve methods. The degradation of TlBr was studied by scanning electron microscopy (SEM) and energy dispersive X-ray spectrometry (EDS). The composition at the electrode area was observed to be different for the negative and positive sides.