Synthesis and Interface Structures of Zinc Sulfide Sheathed Zinc−Cadmium Nanowire Heterojunctions

The large-scale synthesis and growth mechanism of II-B metal nanosponges through a vacuum vapor deposition route

By carefully controlling the experimental parameters, large-scale nanosponges of group II-B metal (Zn and Cd) on Si substrates are fabricated through a vacuum vapor deposition route (VVD). The as-prepared products are systematically characterized by the techniques of powder x-ray diffraction (XRD), scanning electron microscopy (SEM) and transmission electron microscopy (TEM). It is shown that nanosponges are composed of network nanowires, which are 20-250 nm in diameter and hundreds of micrometers in length. On the basis of the time-dependent experimental findings, the nucleation and growth of the nanowires have been elucidated. Moreover, the melting behavior of a single ultrathin zinc nanowire was observed in situ under the irradiation of an electron beam during the TEM measurement for the first time, showing that the melting point of the ultrathin zinc nanowire is significantly lower than that of the bulk.

The synthesis and fabrication of one-dimensional nanoscale heterojunctions

There are a variety of methods for synthesizing or fabricating one-dimensional (1D) nanostructures containing heterojunctions between different materials. Here we review recent developments in the synthesis and fabrication of heterojunctions formed between different materials within the same 1D nanostructure or between different 1D nanostructures composed of different materials. Structures containing 1D nanoscale heterojunctions exhibit interesting chemistry as well as size, shape, and material-dependent properties that are unique when compared to single-component materials. This leads to new or enhanced properties or multifunctionality useful for a variety of applications in electronics, photonics, catalysis, and sensing, for example. This review separates the methods into vapor-phase synthesis, solution-phase synthesis, template-based synthesis, and other approaches, such as lithography, electrospinning, and assembly. These methods are used to form a variety of heterojunctions, including segmented, core/shell, branched, or crossed, from different combinations of semiconductor, metal, carbon, and polymeric materials.