Crystalline Te nanotube and Te nanorods-on-CdTe nanotube arrays on ITO via a ZnO nanorod templating-reaction

Vertically aligned Te nanotube and CdTe nanotube arrays branched with Te nanorods were demonstrated on an indium tin oxide (ITO) substrate via a ZnO nanorods templating-reaction method. By simply changing the etchant type and etching temperature of the ZnO–CdTe core–shell nanocables, the ZnO cores can be selectively etched off and the chemical reaction from CdTe to Te can be well controlled to form pure CdTe or Te nanotubes, or Te nanorods-on-CdTe nanotube nanocomposite arrays. Both the well-crystallized Te nanotubes and the Te nanorods are of hexagonal phase, of which the former have respective wall thickness, diameter and length of ∼60 nm, ∼150 nm and ∼8 μm, and the latter have diameter and length of ∼17 nm and ∼80 nm. Dynamic studies on the structural and morphological evolution from ZnO–CdTe nanocables to the Te-related nanostructures were performed. The formation mechanism of the Te nanorods-on-CdTe nanotube arrays and pure Te and/or CdTe nanotube arrays are discussed.