Synthesis of a one-dimensional atomic crystal of vanadium selenide (V 2 Se 9 ).

The synthesis and nanoscale dispersion of a new one-dimensional (1D) material, V 2 Se 9 , in which chain-shaped molecular units with strong covalent bonds are assembled in a crystal structure via weak van der Waals attraction between chains, were successfully carried out. V 2 Se 9 is synthesized by solid-state reaction and additional heat treatment. The synthesized V 2 Se 9 has excellent thermal stability up to 400 °C and has been experimentally confirmed to be dispersed up to ∼20 nm or less through a specific solvent dispersion. The covalently bonded V 2 Se 9 chain, when isolated from its bulk material, is expected to exhibit unique quantum physical properties owing to the confinement of electrons in the 1D chain structure and the absence of inter-chain interactions, as demonstrated in the case of graphene and other 2D materials. Therefore, the novel 1D material of V 2 Se 9 , as an extension of the current 2D material, is expected to create a new class of materials that will be of significant interest to the materials science and nanotechnology communities for new device applications.