苯并三氮唑类有机光伏材料的结构与激发态性质研究  

Research on the structure and excited state properties of benzotriazole organic photovoltaic materials

作　　者：张祥 赵思宇 刘珂珂[1] 李果果 李珂庆 赵振芳 刘清[1] ZHANG Xiang;ZHAO Si-yu;LIU Ke-ke;LI Guo-guo;LI Ke-qing;ZHAO Zhen-fang;LIU Qing(High&New Technology Research Center,Henan Academy of Sciences,Zhengzhou 450002,China;Zhengzhou Chengzhi Industrial Company Limited,Zhengzhou 450000,China)

机构地区：[1]河南省科学院高新技术研究中心,河南郑州450002 [2]郑州市诚志实业有限公司,河南郑州450046

出　　处：《化学研究与应用》2023年第10期2440-2448,共9页Chemical Research and Application

基　　金：河南省科技攻关项目(222102320294);河南省科技攻关项目(222102320184);河南省科技攻关项目(222102240115)资助。

摘　　要：基于密度泛函理论对6种有机光伏材料使用B3LYP/6-31g+(d,p)方法进行计算,对结构和激发态的诸多性质进行研究。研究结果表明,在基态稳定结构中,M1~M4为反式的平面结构,而M5与M6存在40°以上的二面角,因此z轴有较大的偶极矩分量。而M5与M6激发态分子结构的二面角减小了25°左右,逐渐变为反向平面结构,导致总偶极矩呈现下降的趋势。所有分子的HOMO主要集中于苯环和桥联单元上,而LUMO主要分布在苯并三氮唑环上。平面型分子的HOMO与LUMO对于调控的变化不明显,拥有较大二面角的分子,对于形成内部载流子是较为不利的。在环己烷溶剂模型中对分子的紫外吸收光谱和激发态进行分析,M3的紫外吸收范围较大,有助于提高OSCs的光电转化效率,M5与M6不利于载流子的形成,不利于制备成为OSCs给体材料。所有分子激发态性质均是由HOMO之下的4个轨道和LUMO之上的3个轨道之间决定,这样的激发态性质有利于保证材料的稳定性。这些研究为更好地设计半导体材料提供了良好的理论依据。Six kinds of organic photovoltaic materials were calculated by the B3LYP/6-31g+(d,p)method on the density functional theory,in order to study many properties about structure and excited state.The results show that,M1~M4 are a trans planar struc-tures,in while M5 and M6 have a dihedral angle of more than 40°,which the z-axis has a large dipole moment component in the sta-ble structure of ground state.However,the dihedral angle of M5 and M6 decreases about 25°,and gradually becomes the reverse plane structure,which also make the total dipole moment present a downward trend in the stable structure of excited state.The HO-MO of all molecules are mainly concentrated on the benzene ring and bridging units,while LUMO are mainly distributed on the benzotriazole ring.The HOMO and LUMO of planar molecules are not obviously change for regulation,molecules with large dihedral angle are unfavorable for the formation of internal carriers.The UV absorption spectrum and excited state of the molecule are ana-lyzed in the cyclohexane solvent model.M3 has a large UV absorption range,it is helpful to improve the photoelectric conversion ef-ficiency of OSCs.M5 and M6 are not conducive to the formation of carriers,therefore they are not conducive to the preparation of OSCs donor materials.All excited state properties of molecules occur between the four orbitals below HOMO and the three orbitals above LUMO.Such excited state properties are conducive to maintaining the stability of materials.These studies provide a good oretical basis for better designing semiconductor materials.

关 键 词：有机太阳能电池 密度泛函 结构 激发态 前线轨道 

分 类 号：O641.1[理学—物理化学]