Characterization of ZnSe nanoparticles synthesized by microwave heating process

ZnSe nanoparticles were synthesized for the first time by a microwave heating process using high purity Zn and Se powders in equimolar ratio. Nanoparticles of the title material were obtained within 30 min with high crystallinity. The crystalline phase of the synthesized ZnSe nanoparticles was confirmed by powder X-ray diffraction (PXRD), the crystallite size was calculated using Scherrer's formula and found similar to 33.14 nm. A scanning electron microscope (SEM) also used to determine the size of the nanoparticles which shows an average particle size of similar to 50 nm, in agreement with PXRD. The particle size distribution was in the range of similar to 40 to 60 nm. The Raman spectra have been recorded at ambient temperature, TO and LO phonon modes were observed at similar to 208 and similar to 253 cm(-1) in the ZnSe nanoparticles which showed a clear shifting toward the low frequency relative to bulk values. The optical study was investigated by UV-Vis. Spectroscopy, the optical energy band gap of the synthesized nanoparticles was calculated and found to be 2.99 eV higher than bulk ZnSe (E-g = 2.7 eV) which shows the clear blue shifting by 0.29 eV which may be due to the crystallite size and energy gap confinement. (C) 2009 Elsevier Ltd. All rights reserved.