New Approach to the Synthesis of Bulk and Supported Bimetallic Molybdenum Nitrides

A new and facile method for the preparation of bulk and MCM41-supported bimetallic molybdenum nitrides is described. Both Ni 2 Mo 3 N and Co 3 Mo 3 N are prepared in a one-step synthesis without ammonolysis. A mixed-salt precursor containing HMT (HMT = hexamethylenetetramine), Ni (Co) nitrate, and (HMT) 2 (NH 4 ) 4 Mo 7 O 24 ·2H 2 O is directly converted to bimetallic nitride under a flow of argon at 923 K. The formation process shows that Ni (Co) metal and γ-Mo 2 N are formed first and that they then transform into the bimetallic nitride phase on remaining at 923 K. The HMT is used as a reducing agent and nitrogen source. The metal salts and HMT are initially contained in the precursor, thus allowing us to obtain bimetallic nitride by a one-step synthesis without ammonolysis. To get high surface catalysts, MCM41-supported bimetallic nitrides have also been successfully prepared with this simple method. The ammonolysis is not a prerequisite here, and the bimetallic molybdenum nitride is facile under mild conditions. The results suggest that this novel method possesses the potential to be a general route for the preparation of bimetallic molybdenum nitrides.