Gas phase-based growth of highly sensitive single-crystal rectangular micro- and nanotubes

In this study, we report the preparation of 3,4,9,10-perylenetetracarboxylic dianhydride (PTCDA) micro/nanotubes (M/NTs) by a simple physical vapor deposition (PVD) process, and it was found that tubular structures with a diameter from 300 nm to 5 mu m and lengths up to tens of micrometres were obtained on a glass substrate at a deposition temperature of 350-400 degrees C. Detailed studies revealed that PTCDA M/NTs were formed via curling and seaming of a 2D lamellar structure constructed by virtue of the cooperation of some noncovalent interactions such as pi-pi interactions and H-bonds, and it was a temperature-activated process. Devices based on single PTCDA microtubes with different diameters exhibited resistance decreased by 2 orders of magnitude in reducing hydrazine vapor (even for such a low concentration as 5 ppm). Such a successful application of the PVD process to simple organic molecules and highly efficient performance in devices are expected to provide great opportunities for the formation of diverse functional organic hollow nanostructures.