Synthesis of multilayered composite nanotube heterostructure; SiC-SiO ₂, C-SiO ₂, and C-SiC-SiO ₂ nanotubes

Three types of composite nanotube heterostructures (two double-layered and one triple-layered structure) are synthesized by simple heat treatment, forming SiC-SiO ₂, C-SiO ₂, and C-SiC-SiO ₂ composite coaxial nanotubes. These multilayered composite nanotubes consist of several components with different electrical properties, for example, metal, semiconductor, and insulator components. In particular, C-SiC-SiO ₂ triple-layered nanotubes with metallic, semiconducting, and insulating layers are synthesized for the first time. These multilayered nanotubes can be expected to find applications in nanoscale heterostructure electronic and optical devices.