Perfect mechanical and robust electronic properties of new carbon nanothreads: A first principles study

We have investigated the mechanical and electronic properties of three types of one-dimensional carbon materials: diamond naonthreads (DNTs) and its mutational structure with CC triple bonds insertion (DNTs-C1 and DNTs-C2), using first-principles calculation. Our calculation results indicate that mechanical properties of DNTs can be obvious promoted by CC triple bonds inserted. Based on density function and deformation potential theory, electronic transport properties of DNTs are investigated. We find that DNTs, DNTs-C1 and DNTs-C2 are wide gap semiconductors. And the strain effect on band gap in DNTs, DNTs-C1 and DNTs-C2 weakens successively. Furthermore, the strain effect on carrier phonon-limited mobility in DNTs and DNTs-C1 is very limited. But the electron mobility in DNTs-C2 is very sensitive to compression stress due to the position of conduction band minimum shifted. Due to huge different between electron and hole mobility, DNTs behaves like n-type semiconductor, and DNTs-C1 behaves like p-type semiconductor. Our results suggest that DNTs, DNTs-C1 and DNTs-C2 have a wonderful application in lightweight and high-strength materials. Moreover, considering the wide gap and high mobility, they have potential applications on high-temperature devices, transparent conductors and so on.