Synthesis of Nanocrystalline Zr₃N₄ and Hf₃N₄ Powders from Metal Dialkylamides

Abstract

Abstract A simple process to synthesize Zr 3 N 4 and nitrogen‐rich Hf 3 N 4 powders via ammonolysis of metal dialkylamides, i.e. Zr(NEt 2 ) 4 and Hf(NEt 2 ) 4 , at temperatures below 700 °C is presented. The obtained nitrides have a rhombohedrally distorted NaCl‐type structure, which has previously been reported only for nitrogen‐rich films of these nitrides. Regardless of the atmosphere (N 2 and He), the Zr 3 N 4 starts to decompose above about ∼ 650 °C and achieves the highest decomposition rate at about 900 °C, finally yielding the mononitride ZrN. Both Zr 3 N 4 and Hf 3 N 4 powders are nanocrystalline with the crystal size of about 2 nm.