CdO/ZnO core/shell nanostructures grown from single molecular precursors

Quadrilateral CdO nanoparticles were grown from cadmium cupferronate complex by injecting the precursor dissolved in octylamine into trioctylamine at 220 and 250 degrees C. CdO/ZnO core/shell structures were synthesized with a method similar to that of growing CdO cores by injecting the shell precursor following the growth of cores. The shell growth temperature was adjusted from 160 to 130 degrees C, and the shell precursor supply speed was adjusted from 4 to 8 ml/h. The obtained nanostructures were characterized by X-ray diffraction, high resolution transmission electron microscope, and ultraviolet-visible spectrophotometer. No core/shell structures formed if the shell precursor injection speed was as high as 8 ml/h. A very thin layer of ZnO shells would form on CdO cores if the shell precursor was injected at a speed of 4 ml/h at temperature of 160 degrees C, and the shells had good crystal quality. CdO/ZnO core/shell nanostructures were inclined to be spherical, and no homogeneous formation of ZnO nanoparticles was observed if the shell precursor injection temperature was lowered to 130 degrees C.