Synthesis of CdSe quantum dots in PVA matrix by radiolytic methods

Polymer films of polyvinyl alcohol (PVA) containing CdSe quantum dots of various sizes from 3 nm to 5 nm have been synthesised by the radiation-chemical route using CdSO4 and Na2SeSO3 as the starting materials under a reducing condition. 2 MeV electron beam from an electron accelerator and the gamma radiation from a cobalt-60 gamma chamber were used as the irradiation sources for the syntheses. The particle sizes were small in the case of electron beam irradiation as compared to those in the case of the gamma irradiation. The sizes of the quantum dots were strongly dependent on the absorbed dose rate and the initial precursor concentrations. The CdSe quantum dots exhibit excitonic absorption at room temperature. The films containing these quantum dots were quite stable for months.