Performance of NiO and Ni–Nb–O active phases during the ethane ammoxidation into acetonitrile

Abstract

There is a need to develop catalysts for the direct ammoxidation of ethane to acetonitrile. This work reports a series of bulk Ni–Nb–O catalysts with increasing niobium content, analysing the structure and the effect on acidity and redox properties and how these relate to Ni–Nb interaction. Niobium doping affects NiO lattice leading to progressively smaller unit cell sizes. The Nb/Ni atomic ratio determines the formation of two Nb–Ni–O mixed phases identified by HRTEM, and which Raman bands are identified near 850 cm−1 and 800 cm−1 for a Nb-poor phase and near 800 cm−1 for a Nb-rich Ni–Nb–O one.