Research On Magnetic Field Effect Of Organic Solar Cells

In recent years,the research on the magnetic field effect of organic semiconductor materials has made a lot of progress,which provides a basis for the study of the internal working mechanism and magnetic field effect of organic solar cells.Taking the magnetic field effect of organic solar cells as the research topic,according to the relevant theoretical formulas of solar cell charge transport and organic electron spin,based on the modified drift diffusion model and combined with other secondary models,this paper constructs a semi analytical simulation model,focusing on the influence of external magnetic field on the internal photocurrent and magnetic conductivity of organic solar cells.The main contents are as follows:The theoretical basis related to organic solar cells and magnetoresistance effect is introduced,including organic solar cell principle,spin electron,drift diffusion model,magnetoresistance effect,carrier statistical distribution,mobility model,blackbody radiation approximation model and so on.Based on the drift diffusion model,combined with other secondary models,the J-V formula of organic solar cells is deduced.The original drift diffusion model is modified three times:electric field intensity approximate correction,average carrier concentration correction and degenerate correction.The solution of the modified semi analytical model converges stably,and it is helpful for researchers to study the effects of several key parameters on the internal carrier transport in organic solar cells.The secondary models used include:SRH composite model,Li magnetoresistance model,blackbody radiation approximation model,etc.Finally,the J-V curve of organic solar cell is solved by MATLAB software.Through the simulation of PCDTBT:PC₇₀BM solar cell,the J-V simulation data obtained fits well with the experimental data in the literature,which verifies the accuracy of this model.In addition,the electron current density and hole current density are also simulated,and the effect of Ti O_xthin layer on PCDTBT:PC₇₀BM solar cell is analyzed.At the same time,the spatial distribution of electron and hole concentration in the active layer and the influence of built-in potential on the J-V characteristics of the battery were also studied.Similarly,the J-V characteristics of P3HT:PCBM solar cell are studied by using the simulation model.The simulation data and literature experimental data have also achieved good results,which verifies the accuracy and practicability of this model again.In addition,the spatial distribution of electrons and holes in the active layer of P3HT:PCBM solar cells was also studied.The magnetic conductivity curves of P3HT:PCBM solar cells under different bias voltages are studied by using the simulation model.The simulation data fits well with the literature data.The internal mechanism of magnetic conductivity is analyzed by referring to the relevant literature.Finally,the relationship between bias voltage,hubbard energy and magnetic conductivity is studied.The results of model simulation in this paper fit well with the experimental data,which provides a good reference value for the future research on the J-V characteristics of organic solar cells and the internal mechanism of magnetic field effect.