Study on growth mechanism and optical properties of ZnSe nanoparticles

ZnSe nanoparticles with the cubic zinc blende structure were synthesized by a triethanolamine (TEA)-assisted solvothermal method without surfactants and templates. The effects of the TEA on the growth mechanism of ZnSe nanoparticles were analyzed. Photoluminescence measurements showed that the intensity of the defect-related emission band varied with the volume of TEA, as different types of defects were dominant in the ZnSe nanoparticles. Moreover, the emission band centered at 545 nm was attributed to the recombination of a donor–acceptor pair involving Zn vacancies, while the emission band centered at 668 nm was due to the stacking faults, twinning defects and some point defects. In Raman spectra, a clear shift of the transverse and longitudinal optical phonon modes, as well as a broadening of the longitudinal optical phonon peak were observed for ZnSe nanoparticles.