Ural Federal University: Luminescent Compound Will Help Control Human Exposure
Scientists at UrFU and the Institute of High Temperature Electrochemistry of the Ural Branch of the Russian Academy of Sciences discovered a new property of a well-known ceramic material, zinc aluminate. Today this material is used in optics and in the production of lasers, and chemists managed to expand its application area. They found that the compound, which shows luminescent properties, can be used for dosimetric purposes: as a detector that measures the absorbed dose of radioactive radiation. The advantage of the material synthesized by Ural scientists is its sensitivity to small and medium doses. The results of the study are published in the journal Ceramics International.
“Zinc aluminate is a ceramic material that is actively used in the production of sensors, solar cells, and laser technology. We decided to study its prospects for use as a radiation detector because it has the necessary properties for this purpose. The compound has many structural defects, including oxygen vacancies that can capture beta particles, electrons that escape from atomic nuclei of some radioactive substances during decay,” explains Georgy Starostin, a Research Engineer at UrFU’s Hydrogen Energy Laboratory.
According to the researcher, the small size of aluminate ceramics (a cylinder 1 cm in diameter and weighing 300 mg) allows its use as a pocket radiation detector for small and medium doses. This will come in handy not only at enterprises where people work with radioactive substances, but also for measuring the level of radiation exposure in places with elevated background radiation.
To measure the absorbed dose, zinc aluminate is placed in a location where ionizing irradiation is suspected. Defects, concentrated mainly on the grain boundaries of the compound, capture electrons and release them only when heated. Ceramics are heated in a special experimental setup, which determines the intensity of radiation (thermoluminescence). According to the value of the maximum intensity of the peak on the graph, it is possible to calculate the absorbed dose that a person in that location receives.
“A large number of pores on the ceramic surface, on which the very structural defects capable of capturing electrons are localized, are formed due to the solid-phase synthesis method. We found that the solid-phase method is optimal for the synthesis of zinc aluminate for dosimetric applications. In terms of dosimetric properties, the sample sintered at 1400 °C for five hours is the most promising ceramic for use in radiation detection systems. The synthesis technology is scalable if needed due to its simplicity,” adds Georgy Starostin.