Hierarchically nanostructured vanadium nitride microspheres assembled with porous nanosheets fabricated by a template-free route

In this research, hierarchically nanostructured vanadium nitride (VN) microspheres were successfully prepared by a template-free method. ZnO, behaving as a sacrificial phase, was selectively leached out during nitridation of Zn3(OH)2(V2O7)·(H2O)2 microspheres with NH3, inducing a network structure. The VN microsphere was assembled with porous nanosheets. Extraordinary, the VN microsphere mimicked the morphology of the initial precursor and exhibited a rose-like morphology. The diameter of the microsphere was in the range of 1-3 µm, and the thickness of the porous nanosheets was typically approximately 30 nm. In addition, this facile and novel synthetic strategy can be further extended to the preparation of other hierarchically nanostructured transition metal nitrides.