ZnO Nanostuctures-based Sensitized Solar Cells:Preparation And Performance Study

In order to solve the energy crisis and prevent pollution, the research and preparation of photovoltaic device to transform sunshine into electricity has important scientific significance. As one of the most development potential liquid battery, quantum dot sensitized solar cell is based on the separation of the carrier caused by bandgap coupling which is formed by narrow bandgap and broad bandgap semiconductors. Through constructing core-shell type cable array structure, which uses the transparent conductive glass such as one-dimensional ZnO nanorods array structure to speed up the electron transmission, using the light absorption performance of narrow bandgap semiconductor materials as nano shell to increase the lighting area and reduce the loss of electron transmission distance and interface charge. Therefore, broaden the absorption spectrum of the sensitizing agent and promote the separation and transmission of the charge carrier are important for improving the photoelectric conversion efficiency.This article first has a research on the preparation and electrochemical properties of nano cable core-shell type ZnO/CdSeTe alloy structure. Uses hydrothermal method to prepare the ZnO nanorod array on the transparent conductive glass, and then electrochemical deposition is used to build synthesized composition adjustable CdSeTe alloy shell on the ZnO nanorod array. By changing the deposition in the solution and the proportion of the Se/Te source and deposition time of CdSeTe alloy, the thickness and composition x realizes flexible, in combination with high temperature annealing, the photoelectrochemical properties of the electrochemical battery is effectively improved. The study found that the light absorption edge of the alloy nano cable array first shift red then shift blue with the x value increases. Among them ZnO/CdSeo.3Teo.7nano cable array’s light absorption edge is of-880nm, and the photocurrent reached17.2mA/cm2after the construction of electrochemical battery, which is far higher than that of ZnO/CdTe, ZnO/CdSe alloy nano cable and other components. Further optimization of the shell thickness of ZnO/CdSe0.3Te0.7makes the saturation photocurrent density increased to20.0mA/cm2.Secondly, the three-dimensional nanometer ZnO stacking structure of electrode preparation and electrochemical properties is studied. By hydrothermal method in AZO transparent conductive glass we grow a layer of ZnO three-dimensional nano stacking structure, and then the PEI effect on the growth of ZnO is studied. The AZO conductive glass annealing temperature is analyzed to optimize the annealing temperature, and then by changing the times of hydrothermal method the purpose to adjust the thickness of the ZnO stacking structure is achieved. Through SEM analysis summarizes the relationship between the hydrothermal times and the thickness of the ZnO stacking structure. After the dual optimization of the annealing temperature and the thickness of the ZnO stacking structure, and finally under sensitization of the N719, the open circuit voltage reaches～0.49V, short circuit current～9.51mA/cm2, the fill factor of41.4and a photoelectric conversion efficiency of about2%.