Optical and Structural Studies of Phase Separation in Zn x Cd 1-x Se/C Core/Shell Nanocrystals

摘要: ZnxCd1−xSe/C core/shell nanocrystals with 31–39 nm diameter semiconductor cores and 11–25 nm‐thick carbon shells were synthesized from solid state precursors in large scale amounts. Transmission electron microscopy (TEM) showed striations the that are indicative of a composition modulation, reveal chemical phase separation possible spinodal decomposition within nanocrystals. The optical properties carrier relaxation kinetics examined cathodoluminescence (CL) imaging spectroscopy. As excitation level is increased, filling two‐dimensional phase‐separated Cd‐rich regions leads to partial saturation states before onset higher bandgap homogenous Zn0.47Cd0.53Se regions. In order model calculate quasi‐Fermi levels for electrons holes, random quantum well was used determine hole eigensates