Solvothermal synthesis of urchin-like V–Ti–O hierarchical micro-nanostructures for the catalytic ammoxidation of chlorotoluenes

In the field of heterogeneous catalysis, it still remains a challenge in controlled preparation of micro-nanostructured composite oxide catalysts. In this regard, a series of urchin-like V–Ti–O micro-nanostructures with varying Ti/V molar ratios are successfully synthesized by the reaction between tetrabutyl titanate (TBOT) and vanadyl oxalate via a facile one-step solvothermal process and subsequent calcination. The influences of reaction conditions, such as the ratio of reactant, the acidity of reaction system, and the use of glycol on the morphologies and oxidation state of vanadium are investigated. The results show that urchin-like hierarchical micro-nanostructures are formed, on which a large number of one-dimensional nanobelts radially grow from the center. Vanadium oxide species are highly dispersed on the external surface of the anatase TiO 2 structure. The obtained V–Ti–O catalysts are tested for the ammoxidation of mono- and dichlorotoluenes in gas-phase with molecular oxygen and exhibit high catalytic activity in converting chlorotoluenes to corresponding nitriles.