Vacancy Transport Properties in Boron-Carbon BC3 Nanotubes

The paper presents results of theoretical research into vacancy formation in B type of boron-carbon nanotubes ВСn, where n = 3. The research was performed using the MNDO method within the framework of an ionic-embedded covalent-cyclic cluster model, molecular cluster model and DFT method. We found that when a V-defect (vacancy) is introduced in a boron-carbon nanotube, the band gap of the defective tubules increases. It means that physical properties of materials can be purposefully changed by introducing defects. Vacancy migration along the atomic bonds in the tubule was simulated and vacancy transport properties were studied. It was found that the defect migration along different bonds actually represents the process of carbon or boron ions hopping between their stable states on the nanotube surface. The calculated activation energy values revealed dependence of ionic conductivity in boron-carbon tubules on temperature.