Preparation And Properties Of Morpholgy Controllable ZnO/CdS Quantum Dots

ZnO, which has excellent photoelectric and photocatalytic performance,is a wide and direct band gap semiconductor materials, but it only absorb theUV region light. CdS has excellent absorption properties of visible light, theCdS nanoparticles may be suitable for the sensitization of ZnO to expand itslight absorption range.In this thesis, the ZnO films were prepared on ITO conductive glass bythe electrodeposition method. Four kinds of morphology of the ZnO films,such as vertical grown of the hexagonal rod array, the array of hollow tubular,vertical grown layers and nanoparticles, were obtained. The hexagonal rodarray of zinc oxide nanostructures showed obvious preferred orientation alongthe (002) crystal plane and larger visible light transmittance. The size anddistribution of ZnO hexagonal rod array was successfully controlled byadjusting the technique parameters.CdS quantum dots were prepared on the ZnO nanorods array bysuccessive ionic layer adsorption and reaction. By adjusting the number ofcycles, the amount and coating extent of CdS quantum dots on the zinc oxidesurface can be controlled. The CdS quantum dots sensitized ZnO nanorods array have a9.83mA/cm~2photocurrent intensity, which was80times higherthan that of ZnO nanorods. The degradation rate of rhodamine B of CdSquantum dots sensitized ZnO nanorods array is about50%higer than that ofZnO nanorods arrays.