Different Conjugated Molecules:PC₇₀BM Research On Charge Transfer Mechanism Under External Electric Field

With the vigorous development of the global economy,energy shortages and environmental governance issues are imminent,and the demand for efficient clean energy has become increasingly urgent.Solar energy is considered to be the most effective green resource compared to fossil fuels such as coal,oil,and natural gas with limited resources.However,how to make solar energy efficient use has always been the focus of attention.Polymer solar cells have many advantages,such as low quality,can be used to manufacture flexible semi-transparent devices in large areas,which has aroused the research interests of researchers.After the discovery of light induced electron transfer between the C₆₀0 and the compound was discovered,the researchers began to apply these materials to the preparation of large-area collapsible solar cells,introducing conjugated organics to the photoactive layer and Hole transport layer.Compared with traditional silicon cells,its structure is more streamlined,and organic materials are rich in raw materials,low in cost,and the electrical and optical properties can be adjusted.It can also reduce the cost and increase the conversion efficiency.The electron transfer mode can be directly affected by the electron transfer rate.In this paper,the formula of electron coupling strength is deduced,and the influence of vibration on the coupling strength of electrons is analyzed and verified.This paper studies conjugated polymers?donors?that have recently attracted wide attention.Through the calculation of donors and acceptors,the hidden value of conjugated polymers used in conductive materials and solar cell materials has been analyzed and summarized.Five kinds of naphthofuran molecules with different chain lengths,TTF-dppz and TTF-quinoxaline molecules with different conjugated substituents as donors and PC₇₀BM as acceptors were selected.Using quantum mechanics,density functionals and Gaussian et al.,a series of light-induced charge transfer correlations were calculated.The use of three-dimensional?3D?visualization allows light-induced charge transfer to be processed,allowing a simple and straightforward analysis of charge transfer directions.The polymer structure was adjusted using Gauss View5.0.9 software and Materials Studio software,based on DFT,B3LYP\6-31G?d,p?and PBE1PBE\6-311g?d,p?basis set polymer geometries.Using the excited state of the TD-DFT calculation system,V_daa and charge transfer?ET?were analyzed.Analyze the reorganization energy and free energy of the system based on Marcus theory.The effects of different lengths of conjugated chains and different conjugated substituent compounds and external electric fields on the charge transfer rate were compared.