Solution combustion synthesis of nanostructured molybdenum carbide

A novel approach for the preparation of molybdenum carbide by solution combustion synthesis (SCS) combined with subsequent programmed heating of SCS products was proposed using ammonium heptamolybdate (AHM) and organic reducers (glycine, alanine, glucose, etc.) as precursors. It has been shown that SCS temperature and composition of the products are governed by changing the AHM-organic fuel ratio, the type of organic reducer, the rate of gaseous oxygen flow, and quantity of ammonium nitrate. A solution combustion synthesis method allowed to produce molybdenum carbide at the first stage only from the AHM-glycine system. In the other studied systems, carburization process was stimulated by the subsequent programmed heating of the SCS product, sometimes with addition of a certain amount of carbon source up to 1200 °C with Vh = 20–100°min−1. The catalytic activity and selectivity of Mo2C was tested on the model reaction of isopropyl alcohol conversion. A new phenomenon showing the temperature influence on the selectivity of either propylene or acetone formation was revealed.