Synthesis of transition metal pnictide nanocrystalline powders by mechanochemical reaction

Transition metal pnictide powders have been successfully synthesized by mechanochemical reaction between transition metal and pnictide elemental powders. The reaction enthalpy and particle size influence both the reaction path and rate. A mechanically activated self-sustaining reaction (MSR) was observed in the Mn-P, Co-P and Mn-Fe-P-As systems, while the reaction progressed rather gradually for the Ni-P and Fe-P systems. The occurrence of MSR seems to be related with the nominal adiabatic temperature (−ΔH/Cp) for the corresponding reaction.