Zn₂TiO₄−ZnO Nanowire Axial Heterostructures Formed by Unilateral Diffusion

We present a two-stage fabrication method for Zn 2 TiO 4 −ZnO nanowire axial heterostructures using the site-specific deposition of TiO 2 on the tips of ZnO nanowires, followed by an annealing process. As revealed by the electron microscopy investigation, the cubic spinel Zn 2 TiO 4 single crystal heads possess two kinds of oriented relationships with ZnO nanowires after high-temperature reaction. The reaction between TiO 2 nanoparticles and ZnO nanowires shows a unilateral diffusion characteristic of ZnO into TiO 2 which provides a useful method for rational design and fabrication of nanostructures based on nanostructured phase transformation.