Quasi‐Aligned Single‐Crystalline W18O49 Nanotubes and Nanowires

Quasi-aligned single-crystalline W18O49 nanotubes or nanowires were successfully prepared under different atmosphere pressures. As such, a deficiency in vapor supply plays an essential role in the nucleation of tubular nanostructures. Field-emission measurements showed a threshold of 6.2 Vμm-1 for the W18O49 nanowire films, indicating that they were excellent field emitters.