FEFU Team Awarded Russian Material Grant for Manufacturing

A research team led by Denis Kosyanov at the Far Eastern Federal University (FEFU) has received grant funding from the Russian Foundation for Basic Research (RFBR) for developing and standardizing manufacturing processes for materials based on laser ceramic-thermoelectric heterostructures.

During the three-year RFBR grant period, the scientists will synthesize the basic nanopowders, establish sintering parameters of the laser-ceramic layer with a thermoelectric component, elaborate the method for their combination into unified material, standardize material functionality, and put it into practice. For the production of heterostructural ceramics, the innovative method of reactive vacuum sintering will be applied. Yttrium-aluminum garnet and strontium titanate were proposed as sintering components.

The methods applied by the team remove many principal restrictions, which are an innate part of monocrystal growing for laser systems. By incorporating the laser environment with a thermoelectric one, the combined ceramic structures will improve the performance characteristics of the final material in several ways, such as active and passive cooling, as well as a reduction in thermal stress, providing high pumping efficiency, peak radiation power, and a high material destruction threshold.

“The fundamental scientific task of the project is to establish the regularities of the joint sintering of laser and thermoelectric nanoceramics, which are different in terms of the crystal structure and phase composition,” Kosyanov said. “The task is further complicated by the fact that the key properties of the ceramic thermoelectrics are determined by the characteristics of a two-dimensional electron gas localized along the grain boundaries of SrTiO₃ and TiO₂ grains. In other words, a high Q-factor of similar thermoelectrics is possible only when we create a structure where the SrTiO₃ and TiO₂ grains are located in a checkerboard order throughout all the volume of the material. When this problem is solved, it will be possible to manufacture complex composite structures in a single technological cycle.”

The RFBR is a national science funding body of the Russian government.