Research On The Application Of Nanostructure In P3HT:PC₆₁BM System Organic Solar Cells

As the basic element and important guarantee for the sustainable development of human society,energy plays a decisive role in the development of material basis and civilization,which is an important part of the national development strategy.Low-cost,sustainable,and low-polluting clean energy has attracted wide attention from all over the world,and solar energy is the largest proportion of clean energy reserves.Therefore,the use of photovoltaic technology to realize the utilization of solar energy is a hot spot of current research.Organic Solar Cells(OSCs)is the device that use organic molecules or polymers to convert light energy into electricity,the materials of OSCs are diverse and easily available.In addition to the traditional advantages of translucency and low cost,OSCs can be used in flexible electronic systems,which has a wide range of application potential.However,the current research on organic solar cells also faces many problems,including low exciton transmission efficiency,poor long-term stability of devices,low yield of large-area deposition,and low energy conversion efficiency.Low dimensional nanomaterials have excellent physical and chemical properties and have great potential in the application research of improving the performance of photovoltaic devices and other photovoltaic devices.In this paper,three different kinds of nanoparticles were prepared:carbon quantum dots,tin dioxide nanoparticles,and methylamine lead iodide perovskite quantum dots.After that,these low-dimensional nanomaterials were applied to organic solar cells.The influence of different structures on the performance of the device was studied,and the mechanism was analyzed.The effects of different structures on the device performance were explored.And the related influence mechanism was also studied.The main contents of this paper includes:Carbon quantum dots(CQDs)were prepared by microwave hydrothermal assisted method.The CQDs optimized devices with the active layer system of P3HT:PC₆₁BM:CQDs and the contrasted original devices were prepared.The research results show that by adding the third component CQDs to the P3HT:PC₆₁BM blend system,the absorption intensity of the device for sunlight can be effectively improved,and at the same time the carrier transport in the active layer can be enhanced.The main factors that enhance the performance of CQDs optimized devices are the generation of multiple excitons,the charge transport,the energy cascade between the active layer and the acceptor,the secondary fluorescence absorption caused by photoluminescence and the additional light absorption.Tin dioxide (SnO₂)nanoparticles with hollow core-shell structure were prepared by carbon sphere template method.The optimized device with SnO₂ as electron transport layer and the contrasted original devices were prepared.By adjusting the process parameters of SnO₂ nanoparticles to optimize the device performance.The best spinning conditions of the device were obtained as followed:times:1;speed:3000 rpm;time:60s;concentration:2 mg/m L.The UV-vis absorption and photoluminescence spectra of SnO₂&non-SnO₂ multilayer show that the enhancement of the device performance is mainly attributed to the enhancement of the light absorption intensity,the increasement of the electron hole disintegration rate and the improvement of the electron transport property.The methylamine lead iodide perovskite quantum dots(MAPbI₃ QDs)were prepared by the room temperature ligand-assisted reprecipitation method.The MAPbI₃QD optimized devices with the active layer system of P3HT:PC₆₁BM:MAPbI₃ QDs and the contrasted original devices were prepared.The results show that the leakage current can be effectively reduced by adding MAPbI₃ QDs into P3HT:PC₆₁BM active layer system.However,the short-circuit current density decreases rapidly because of organic ligands such as oleic acid and octylamine used in the preparation of MAPbI₃ QDs,which leads to the performance degradation of the device.Then,the effect of the device by adding the MAPBI₃ QDs as the anode buffer layer between the PEDOT:PSS and active layer was studied.The results show that the performance of the device reached the best when the concentration of MAPbI₃ QDs toluene solution is 0.5 mg/m L.The absorption spectrum and photoluminescence spectrum of the multilayer film show that after adding MAPbI₃ QDs as the anode buffer layer in the organic solar cell,the charge transfer and carrier recombination of the device has been improved,leading to a good device performance.