Growth kinetics of CdSe nanocrystals synthesized in liquid paraffin via one-pot method

摘要

The cadmium selenide (CdSe) nanocrystals are synthesized in liquid paraffin via one-pot method. The growth kinetics of the nanocrystals is investigated by the measurements of their ultraviolet-visible absorption and fluorescence emission. The results show that very fast growth occurs linearly for the nanoparticles regardless of the molar ratio of Cd to Se until a reaction time of approximately 60 s, followed by essential growth rate decrease. The nanocrystals thereafter possess a two-stage kinetic feature consisting of a rapid growth within approximately 30 min and a slow growing up to 10 h. The particles size is not governed by the reaction temperature but by the molar ratio of Cd to Se. From the viewpoint of both strong fluorescence emission and saving in raw materials, a reaction temperature of 200 C and a molar ratio of Cd to Se of 4/1 are appropriate for the synthesis of the CdSe nanocrystals.