Synthesis, Characterization, and Growth Mechanism of Self-Assembled Dendritic CdS Nanorods

A simple evaporation-condensation method was used to investigate self-assembled CdS nanorods with different geometrical configurations. At the evaporation temperature of 800 °C, the growth of branched CdS structures with multi nanorod arms along the [0001] direction was observed. However, at 1000 °C, dendritic arrays of parallel CdS nanorods were formed along the [0001] direction. The diameters of the nanorods range from 30 to 500 nm and their lengths from 1 to 5 μm. A series of electron microscopy characterization results suggests that the growth of both types of CdS nanorods is governed by the vapor-solid growth mechanism. The formation of CdS nanorods with various morphologies is attributed to the intrinsically anisotropic growth of wurtzite CdS structure along the [0001] c axis as well as the varying supersaturation of CdS vapor with the evaporation temperature.