Enhanced Thermoelectric Properties of Core/Shell Heterostructure Nanowire Composites

摘要

The formation of heterostructures in one-dimensional (ID) nanostructures is of particular significance with respect to potential applications as building blocks for nanodevices. With the development of the vapor phase deposition technique, various heterostructure nanowires with axial or radial modulated compositions related to Si, Ge, and I1I-V based compounds have been realized by combining the vapor-liquid-solid (VLS) mechanism with a heteroepitaxial growth process. However, there are still many other functional materials that are difficult to grow into ID heterostructures by vapor phase deposition. Thus, it is of great urgency and importance to exploit alternative routes appropriate for ID heterostructure growth of these materials in order to manipulate the functionality of the related nanodevices. The solution phase method has been considered as a powerful strategy for various nanocrystal heterostructure growth, however, only limited reports indicate the rational synthesis of axial heterostructure nanowires and it remains unknown about the ID radial heterostructure growth, where much effort should be devoted. In this work, we try to indicate that it is possible to develop a general strategy to synthesize ID radial heterostructures by introducing epitaxial growth into a solution phase method. The enhanced thermoelectric properties of the obtained nanowire composites are found.