3. Results and discussion
We have previously synthesized CdSe nanoparticles in the
aqueous tert-butanol solution containing equimolar (5 mM each)
[Cd(NH3)4]SO4 and Na2SeSO3 upon irradiation with 7 MeV electron
beam, which are present in the spherical agglomerated forms of size
about 100 nm, due to the absence of any capping agents there [5,6]. In
the present work, the same concentrations of these precursors were
taken in the water pool of the CTAB microemulsions. Thus, the
radiolytic product is expected to be CdSe nanoparticles only. This is
evident from the instantaneous change of microemulsion from
colorless to greenish-yellow upon irradiation, which was otherwise
not observed in normal chemical route. The CdSe nanomaterials were
characterized by optical absorption measurements. The optical
absorption spectra of the unirradiated and irradiated microemulsions
containing CdSe nanomaterials are shown in Fig. 1. The CdSe
nanomaterials clearly exhibit excitonic absorption peaks around
420–425 nm. The band gap values and the sizes of the primary CdSe
nanoparticles were estimated from the absorption spectra by using
Braus equation (Eq. (1)) as shown in Table 1.