Tunable Mechanical and Electrical Properties of Coaxial BN-C Nanotubes

Heterostructures provide a great chance to tune the properties and functions of a nanomaterial, e.g., its mechanical and electrical properties, and thus allowing for the design and realization of novel nanoelectromechanical devices. Boron nitride and carbon nanotubes, with similar structure and mechanical properties but dramatically different electrical properties, are ideal candidates for investigating nanoscale heterostructured materials. In this work, graphitic C‐coated BN nanotubes (BN‐C NTs) were synthesized and their mechanical and electrical properties were simultaneously measured using in situ high‐resolution transmission electron microscopy (TEM). As a function of the coated carbon content, the elastic modulus obtained from second order harmonic resonance of heterostructured nanotubes could be tuned from ∼140 to ∼700 GPa, and their electrical resistivity could be adjusted within three orders of magnitude from ∼0.16 to ∼2.5×10−4 Ω · m. This work opens the way for making custom‐designed heterostructures for the requirements of specific applications.