Synthesis And Photoelectric Properties Investigation Of Nano-Micro Structure Cu₂O, ZnO Films

One of the main problems the world facing today is the new energy development and utilization. In solar research fields, explore potential application of new materials, film solar cells, and seek improve its photoelectric conversion efficiency way is extremely important research direction. Although there are many types of solar cell, the main problems are the low photoelectric conversion efficiency, complex preparation technology, poor stability and environmental pollution. In order to improve the photoelectric conversion efficiency, reduce the cost, improve the stability of solar cells and solve the problem of environmental pollution, we improved the solar cell preparation technology, developed a new film solar cell materials. We synthesized Cu2O, ZnO and Cu2O/ZnO compound films and studied their photoelectric properties. The main content and innovation of this thesis are listed as following:1. We studid the Cu2O electrochemical behavior by cathodic reduction technology on transparent conductive glass substrate and systematically discussed the effect of several reaction factors on the morphologies of electrodepositing Cu2O thin films. The possible formation mechanism of different morphologies has been discussed.2. The Cu2O films photoelectric performance were were also measured with electrochemical workstation using three electrode systems. It is found that the dendritic Cu2O film has better light response characteristics; the photoelectric conversion efficiency is higher than other morphology Cu2O films as electrode material of solar cells.3. ZnO nanorod flims were synthesised on FTO surface using electrochemical and hydrothermal methods, respectively. The crystal orientation is along [002] direction. The ZnO nanorods arrarys synthesized using hydrothermal method are long and dense. In addition, the photoelectric conversion efficiency of ZnO nanorod synthesised by hydrothermal method is greater than ZnO nanorod synthesised by electrochemical method. The length of ZnO nanorod is also influence the photoelectric conversion efficiency. When the length of ZnO nanorod is 3.0μm, the photoelectric conversion efficiency is the highest.4. The Cu2O/ZnO compound film were prepared by two step electrochemical method. The photoelectric performance of the composite films were investigated by adjusting the size, shape and thickness of Cu2O nanoparticles. The results show that the introduction of small Cu2O nanoparticles can improve the separation efficiency of light born carriers. The performance of core-shell structure Cu2O/ZnO compound film electrode has improved comparing to Cu2O film electrode and displayed superior perfermance than that of single ZnO electrodes. If the amount of Cu2O nanopaticles is more, it will become the compound center of electron-hole and reduce the photoelectric properties of Cu2O/ZnO compound film.5. The Cu2O/ZnO compound film were preparaed with ZnO nanrods synthesised by hydrothermal method as the base. The photoelectric performance of the composite films were investigated by adjusting the size, shape and thickness of Gu2O nanoparticles. The results show that the changes tendency of composite films photoelectric conversion efficiency is similar to that the composite films synthesised with two steps electrochemical methods. The photoelectric conversion efficiency of composite film is highest when Cu2O nanoparticles is lesser.6. Cu2O/ZnO composited film heterojunction solar cells wre formed with ZnO nanrods synthesised by hydrothermal method through simple processing. The photoelectric performance and the response characteristics of heterojunction film solar cells were investigated. Further more, we also discussed the photoelectric conversion mechanism.7. We analysised the influence of the two different morphology ZnO nanorods on the photoelectric conversion efficiency. The results show that the smooth and dense ZnO nanorods film can not only solve the problem of short circuit but also can improve the photoelectric conversion efficiency. This nanorods and its composite film have application prospect in optoelectronic devices.