Preparation and optical properties of dispersible ZnSe nanocrystals synthesized by high energy ball milling

ZnSe nanocrystals have been successfully synthesized by high energy ball milling method. X-ray diffraction patterns show a single zinc blende structure formed in the milling process. HRTEM images confirm that the formation of the ZnSe nanocrystals synthesized by high energy ball milling have a wide crystals distribution (3–20 nm). Using the aqueous solutions of Na3PO4, (NaPO3)6 and Na4P2O7 to disperse the 40 h-milled samples, we have observed the gradual blue-shift of the absorption edge along with the different centrifuging speed. In PL spectras, two main bands peaked at about 1.95 and 2.35 eV are observed, the former band is related to the VZn defects emission; and the latter is related to the VSe defects emission. The VSe defects emission does not depend on the dispersants, but the VZn defects emission changes in different dispersants.