Shape control of CdSe nanocrystals with zinc blende structure.

Systematically shape-controlled synthesis of inorganic nanocrystals has attracted increasing attention recently for both fundamental and technological interest. The shape evolution of CdSe nanocrystals with wurtzite structure in a unified method has been previously well studied, while the study on shape evolution of CdSe nanocrystals with zinc blende structure still remains challenging. Here, we demonstrate a systematic shape variation of zinc blende CdSe nanocrystals in a modified organometallic approach, in which distinct shapes of cube-shaped, sphere-shaped, tetrahedron-shaped, and branched CdSe nanocrystals with high yield and good uniformity are obtained. The crucial factor that influences the shape-controlled process is the reactive temperature. This wide variation of shapes provides important information about the growth of CdSe nanocrystals, and it can also help in the shape-controlled synthesis of other nanocrystals that are bound with uniform crystal planes.