Aqueous Solution Method Preparation Of Organic Solar Cell Interface Layer And Research On Photoelectric Properties

After entering the 21st century,the gradual depletion of fossil energy reserves and the resulting environmental pollution problems make people want to find a clean and sustainable new energy as soon as possible.The use of photovoltaic technology to collect energy from the sun is one of the best technologies to overcome the growing global energy demand.Benefiting from the advantages of light weight,good flexibility,high cost-effectiveness,mild processing conditions and synthetic versatility,organic solar cells（OSCs）have good application potential in flexible wear and photovoltaic building integration and have become a research hotspot in the current energy field.One of the disadvantages of organic solar cells is that their photoelectric conversion efficiency is still not satisfactory,and there is a certain gap compared with the most widely used silicon-based solar cells.The morphological characteristics of the interface layer and the active layer have a great influence on the efficiency of organic solar cells.In this article,the device structure is basically ITO/ZnO/Active Layer/MoO₃/Ag,and the main tasks are as follows:In terms of device interface engineering,to optimize the widely used electronic transport material zinc oxide（ZnO）,this paper designs an aqueous solution method for preparation.This improves the microscopic morphology of the ZnO film,thereby enhancing the ability of ZnO to transport electrons in the battery device,and ultimately improving the conversion efficiency of the device.According to the characterization of ZnO thin films,we found that:compared with the ZnO thin films prepared by sol-gel method commonly used by many research teams,the ZnO thin films prepared by aqueous solution method have fewer structural defects and larger surface roughness.These both contribute to the transmission of carriers in the device,thereby improving the short-circuit current of the device,and finally achieving the goal of improving the photoelectric conversion efficiency of the device.The average devices performance of ZnO prepared by sol-gel method is only 11.13%,while the average performance of devices based on ZnO prepared by the aqueous solution method has increased to 11.60%.In contrast to the devices based on ZnO prepared by the sol-gel method,the device performance can be further improved after 20 days of placement of the ZnO precursor prepared by the aqueous solution method,and the average performance of the device is up to 12.33%.In the aspect of structural optimization of active layer,the performance differences of organic solar cells with different mixing ratio of solvents in the precursor solution of active layer were studied.Based on the structural characterization and the optical test of the active layer,and the electrical performance test of the device,the reason for the high conversion efficiency of the device based on doping 20%chloroform is analyzed.In the end,devices better than pure chlorobenzene-based devices were prepared,and the performance reached 11.09%.The improved performance is mainly due to better absorption capacity to the spectrum,more stable charge transfer and fewer interface defects.Overall,compared with the devices based on pure chlorobenzene in the control group,the devices mixed with 20%chloroform had better performance in terms of open-circuit voltage and short-circuit current.In summary,the two optimization methods of designing a new process to prepare a ZnO electron transport layer and using a mixed solvent in the active layer provide new ideas for improving organic solar cells.