Phonon modes and activation energy of Fe-doped CdSe nanoparticles

Nanoparticles of pure and iron (5% and 10%) doped cadmium selenide (CdSe) have been synthesized by soft chemical route and are found to have cubic structure. EDAX analysis supports the inclusion of Fe into CdSe nanoparticles. The average particle size of pure and doped CdSe is found to be ~5 nm. The band gap of the materials is obtained using Tauc relation to UV–visible spectra and found to be about 2.23, 2.14 and 2.1 eV respectively for pure and Fe (5% and 10%) doped CdSe. The observed peaks at 546 nm and 436 nm in the photoluminescence spectra of the samples correspond to 1s–1s transition and its spin orbit component respectively. The Raman and infra-red spectra of the samples are analyzed to obtain the vibrational modes of the samples. The Kissinger equation is applied to the thermo-grams of differential scanning calorimeter to calculate the activation energy of pure and Fe doped CdSe nanoparticles. The frequency dependent conductivity spectra of the samples are found to follow the power law.