In the wake of the discovery of carbon nanotubes (CNTs) in 1991 (Iijima 1991), the exploitation of other materials of a similar cylinder structure began. ough hexagonal boron nitride (hBN) has the closest structure to graphite, the rst non-CNTs discovered were not boron nitride nanotubes (BNNTs) but metal dichalcogenide tungsten disulde (WS2) nanotubes, which were produced in 1992 (Tenne et al. 1992). e BNNT structure was theoretically predicted in 1994 (Blase et al. 1994; Rubio et al. 1994), and the successful experimental synthesis of cylindrical BNNTs was reported by a Berkley laboratory 1 year later (Chopra et al. 1995). Since then, BNNTs have become the most important non-CNTs and aroused great research attention, as evidenced by the increasing number of publications and patents (Golberg et al. 2007a).