This work describes the experimental procedure of a purification method of BiI_3 powder, aiming a future application of these semiconductor crystals as room temperature radiation detector. The Repeated Vertical Bridgman Technique applied to the purification, based on the melting and nucleation phenomena. An ampoule filled with a maximum of 25% by volume of BiI_3 powder mounted into the Bridgman furnace and vertically moved at a speed of 2 millimeters per hour, inside the furnace with programmed thermal gradient and temperature profile, at a maximum temperature of 530°C. The reduction of the impurities in the BiI, after each purification procedure, analyzed by the Instrumental Neutron Activation Analysis (IINAA), in order to evaluate the efficiency of the purification technique established in this work, to trace metal impurities. It demonstrated that the Repeated Bridgman is effective to reduce the concentration of many impurities in BiI_3, such as Ag, As, Br, Cr, K, Mo, Na and Sb. The crystalline structure of the BiI_3 crystal purified twice and three times was similar to the BiI_3 pattern. However, for BiI_3 powder and purified once, an intensity contribution of BiOI observed in the diffractograms.
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