Narrowing the size distribution of CdTe nanocrystals using digestive ripening

Abstract

Digestive ripening of polydispersed colloidal CdTe nanocrystals is performed which results in monodispersed nanocrystals (NCs) as studied by optical spectroscopy. Optimization of ligand and refluxing time is carried out. Monodispersed NCs are obtained using mercaptopropionic acid (MPA) as a digestive ripening agent at a refluxing time of 1–2 h. Digestive ripening of CdTe NCs, which are less polydispersed, is also executed and it leads to more monodispersed NCs. In all the cases, there is a shift of maximum emission wavelength of CdTe NCs after digestive ripening that may be due to Ostwald ripening along with digestive ripening.