Exfoliation and Characterization of V(2)Se(9) Atomic Crystals

Mass production of one-dimensional, V(2)Se(9) crystals, was successfully synthesized using the solid-state reaction of vanadium and selenium. Through the mechanical exfoliation method, the bulk V(2)Se(9) crystal was easily separated to nanoribbon structure and we have confirmed that as-grown V(2)Se(9) crystals consist of innumerable single V(2)Se(9) chains linked by van der Waals interaction. The exfoliated V(2)Se(9) flakes can be controlled thickness by the repeated-peeling method. In addition, atomic thick nanoribbon structure of V(2)Se(9) was also obtained on a 300 nm SiO(2)/Si substrate. Scanning Kelvin probe microscopy analysis was used to explore the variation of work function depending on the thickness of V(2)Se(9) flakes. We believe that these observations will be of great help in selecting suitable metal contacts for V(2)Se(9) and that a V(2)Se(9) crystal is expected to have an important role in future nano-electronic devices.