Study of lead iodide semiconductor crystals doped with silver

Lead iodide PbI2 is a promising material for X-ray and γ detectors. We report on the development and optimization of the method of direct synthesis for the preparation of PbI2 single crystals, purification by zone melting, and growth technique by using the Bridgman–Stockbarger method. We further report on addition of silver as admixture during synthesis in order to study its influence on properties of the prepared material, and on the possible formation of polytypes. The prepared lead iodide has been characterized by measurements of electrical resistivity and low-temperature photo-luminescence. X-ray diffraction has been used to monitor the crystallographic structure. It has been shown that Ag admixtures have changed resistivity of the PbI2 and has not influenced the basic polytype.