Microwave-Assisted Self-Propagating High-Temperature Synthesis of Fine-Particle Bi4Ge3O12

Abstract

A novel process has been developed for the preparation of Bi₄Ge₃O₁₂ (BGO) by self-propagating high-temperature synthesis. In this method, microwave radiation is used for the first time to heat organic fuel (urea), which allows its decomposition to be uniformly activated throughout the reaction mixture. The key synthesis parameters are the pH of the medium, the volume of the liquid phase in the system, and the way in which the starting mixture is homogenized. Varying these parameters has made it possible to reduce the synthesis time to 3 min. We have obtained BGO samples consisting of quasi-spherical particles, potentially attractive for the fabrication of scintillating ceramics. In addition, we have synthesized powders that have an order of magnitude better kinetic scintillation characteristics in comparison with single-crystal BGO and are thus interesting for designing scintillating materials for highly sensitive detectors.