Marvin Cohen and Alex Zettl have published a small review of boron nitride nanotubes [Physics Today 63 (11), 34-38 (2010)]. Two potential applications loom. The authors point out that these nanotubes (abbreviated BNNT) show field emission that is unusually stable compared to carbon nanotube field emission. Also, BNNT field emission closely follows the Fowler-Nordheim law. The implications to cold field emission device construction are obvious.
Furthermore, the BNNT bandgap can be tuned by application of an electric field transverse to the tube axis. At zero applied voltage, the gap is around 5 eV. At sufficiently large applied voltage, the band gap collapses to 0 eV. Perhaps one may use a BNNT as a transistor channel based on this giant Stark effect.
Other electronic applications may arise from the peculiar spatial localization of the lowest conduction band. It is physically situated in the tube, leading lightly doped BNNTs to act like plumbing for nearly a free electron gas.