Growth Kinetics and Optical Properties of ZnSe Nanocrystals

Abstract

Cubic blende ZnSe nanocrystals (NCs) have been prepared by a low-cost, green, fast, and mass-production route (water bath and hydrothermal conditions using Se and Zn(NO3)2 aqueous solution as the precursors). By changing the hydrothermal temperature and time, we managed to grow ZnSe NCs with diameters varying from 3 nm to 40 nm, among which those of ZnSe NCs with the grain size of 27 nm are more uniform. It is observed that the growth kinetics of ZnSe NCs is influenced strongly by hydrothermal temperature and time, and absorption edge blue-shift occurs as the average size of the NCs changes. The ZnSe NCs growth progress (Ostwald ripening) were observed in the HRTEM image. The room-temperature PL spectrum shows a strong emission band at around 464 nm and also some other deep-level defect emission bands. In addition, the findings point to a valuable role for sufficient NaOH in the preparation of pure ZnSe NCs.