The Fabrication Of Zinc Oxide Arrays And Its Application In Photovoltaic Devices

Zinc oxide is a kind of wide band-gap semiconductor which has attracted extensive interest in the field of electrical and optical devices because of its multi-functionality. Electrochemical assembly is a simple and convenient method, has been extensively used in the synthesis of many different types of materials. It has several advantages such as low processing temperature, higher deposition rates, controllable film thickness and morphology.This dissertation was focused on the growth of ZnO thin films and nanoparticles using electrochemical assembly method, studying their physical properties, such as the structural, optical and electrical properties.Nonionic polymer poly (ethylene oxide) (PEO) was introduced into the zinc nitrate electrolyte to modulate the crystal growth and the morphology of ZnO by electrodeposition process. The PEO assistant oriented grown mechanism was put forward in this paper, different attached strength according to different crystal facets result in anisotropic grown activities between side facet and end facet.The ZnO arrays prepared by the electrochemical assembly method can be used as electron transportor in the solar cell, which can enhance the device's performance. The bulk-junction type solar cell with the structure ITO/ZnO/PAT6:PCBM/Au was successfully fabricated. The cell's photovoltaic performance was improved by inserting the oriented ZnO nanorod layer in the device. A device with a power coversion efficiency of 1.71% was obtained after optimizing the distribution of ZnO nanorods and the device's annealing condition.In order to explore the effect of ZnO in the device further, different interpenetrating type devices with different structured ZnO were compared. The results implied the oriented porous structured ZnO has more contribution to the device's performance compared to the flat structured ZnO. Double-layer ZnO structure was firistly used in the interpenetrating layer-layer type solar cell with the structure of ITO/double ZnO/C60/PAT6/Ag. Under AM1.5 irradiation, the device exhibits the excellent performace with a power coversion efficiency of 1.31%, a short circuit current of 7.74 mAcm-2, a open circuit voltage of 0.40 V and a fill factor of 41%. According to the photoconductive theory, a theoretic model about estimating the contribution value to the device's photovoltaic performance was set up. Beae on this model, different devices with different structured ZnO were analysed, some new plans according to this topic was put forward.