New routes to molybdenum nitrides and oxynitrides: preparation and characterization of new phases

Abstract

This paper presents the synthesis of new forms of molybdenum nitride and oxynitride. A face-centred cubic γ-Mo2N type oxynitride phase with excess nonmetal content is prepared by the reaction of ammonia with MoO3 and is characterized by X-ray and neutron diffraction. Its composition, surface area, and morphology depend on the synthesis conditions. The reaction between MoCl5 and calcium nitride in a flux leads to a new Mo2N structure type isotypic with pseudohexagonal α-Mo2C. Starting from MoS2, the products of the reaction with ammonia are two phases related to hexagonal δ-MoN depending on the reaction conditions.