Synthesis of TlBr powder for preparation of room temperature radiation detectors by co-precipitation method

The thallium bromide (TlBr) powder, which is used for TlBr single crystal preparation of room temperature radiation detectors, is synthesized from thallium nitrate (TlNO₃) and hydrobromic acid (HBr) by co-precipitation at room temperature. The phase of the obtained powder is identified by the powder X-ray diffraction (XRD) pattern. Morphology by scanning electron microscope (SEM) characterization illustrates that the powder is uniform with no agglomeration. The influences of experimental parameters, such as the drying temperature, the concentration of the hydrobromic acid and the reactants mol ratio on the Tl/Br ratio of the TlBr powder were studied, for a better control of Tl/Br ratio in the resultant powder. The multiplex side reactions and the van't Hoff equation are employed to analyze the phenomena. Linear relationship is established between the mol ratio of reactants and the Tl/Br ratio in obtained TlBr powder.