Studies on the thin films of zinc oxide–carbon 60 core–shell quantum dots

Thin films of zinc oxide–carbon 60 (ZnO–C₆₀) core–shell quantum dots (QDs) prepared by a simple chemical method were deposited on to a cleaned glass substrate using the spin-coating method with different deposition speeds. Prior to the deposition, ZnO–C₆₀ QDs (in powder form) were studied using a transmission electron microscope (TEM) to determine average particle size and core–shell structure. The lattice parameters and unit cell volumes were determined by analyzing the TEM–selected area electron diffraction pattern. The deposited films of ZnO–C₆₀ were characterized using atomic force microscopy (AFM) and profilometry for the surface topography and an ultraviolet–visible spectroscope for their optical behaviour. AFM micrographs show the decrease in the root mean square roughness with an increase in the deposition speed and the films exhibit blue shift in E_g value due to the molecular interaction of the ZnO and C₆₀ layer and the quantum confinement effect.