The study of optical characteristic of ZnSe nanocrystal

Abstract

Nanocrystal ZnSe material was prepared in a triethylamine solvent using the modified solvothermal method in which potassium borohydride, a reducing reagent, is employed. Compared with the bulk ZnSe, the steady absorption edge and photoluminescence peak of nanocrystal ZnSe shift toward high energy. With the decrease of nanoparticle size, the probability of inelastic collision between electron and nanoparticle surface increases, which results in the enhancement of the intensity of electron–phonon coupling and the decrease of electron–phonon scattering time. In the lower temperature range (13–100 K), the transition probability between singlet state and triple state rapidly increases with the increase in temperature. With the further increase in temperature (100–292 K), the radiative recombination between singlet state and ground state is dominant. The competitive non-radiative recombination between singlet state and triple state is suppressed, therefore, the radiation decay time of singlet state changes slightly.