High Temperature and Pressure Synthesis, Compression Behaviors and Thermal Expansion of Novel Transition Metal Nitrides

Abstract

Pressure is one of the thermodynamic parameters together with the temperature to control the stability of materials. Ultra-high pressure in more than GPa regions allows us to obtain novel transition metal nitrides. This review shows a synthesis system under ultra-high pressures and high temperatures called laser-heating diamond anvil cell system in the first part. Then, our recent research results of the first synthesis of a novel niobium nitride, U₂S₃-type Nb₂N₃ are described. In the second part, compression and thermal expansion behaviors of the U₂S₃-type Nb₂N₃ are shown and compared with each other. Besides, the high pressure in-situ XRD and low temperature in-situ XRD measurement systems in the Aichi Synchrotron Radiation Center (Aichi SR) are also described briefly.