Shape-controlled synthesis of vanadium diselenide

VSe2 is a typical layered semimetal TMDC, and was thought to be difficult to synthesize for many years. By changing the concentration of precursors and reaction steps in the hydrothermal method, here we successfully synthesize three different shapes of VSe2: nano-hydrangea (NH), nano-dandelion (ND) and hexagonal disk (HD). The as-prepared VSe2 HDs have a singlecrystalline structure compared with the poly-crystalline structure of NHs and NDs. The asprepared VSe2 in these three shapes also demonstrates apparent differences and intrinsic properties both in the nitrogen adsorption-desorption characterizations and UV-vis absorption analysis. Possible growth processes and mechanisms are put forward in detail to further inspire shape-design in other nanoscale materials.