有机光伏异质结氟化苯三唑聚合物给体/十环熔合非富勒烯受体的理论研究  

Theoretical Study on Organic Photovoltaic Heterojunction FTAZ/IDCIC

作　　者：杨兵 张材荣[1] 王宇 张梅玲[1] 刘子江 吴有智[3] 陈宏善[4] Bing Yang;Cai-rong Zhang;Yu Wang;Mei-ling Zhang;Zi-jiang Liu;You-zhi Wu;Hong-shan Chen(Department of Applied Physics,Lanzhou University of Technology,Lanzhou 730050,China;Department of Physics,Lanzhou City University,Lanzhou 730070,China;School of Materials Science and Engineering,Lanzhou University of Technology,Lanzhou 730050,China;College of Physics and Electronic Engineering,Northwest Normal University,Lanzhou 730070,China)

机构地区：[1]兰州理工大学应用物理系,兰州730050 [2]兰州交通大学物理系,兰州730070 [3]兰州理工大学材料科学与工程学院,兰州730050 [4]西北师范大学物理与电子工程学院,兰州730070

出　　处：《Chinese Journal of Chemical Physics》2023年第2期199-210,I0055,共13页化学物理学报（英文）

基　　金：This work was supported by the National Natural Science Foundation of China(No.11964016);the HongLiu First-class Disciplines Development Program of Lanzhou University of Technology.The authors were grateful to the National Supercomputing Center in Shenzhen.

摘　　要：本文为了理解由十环熔合非富勒烯受体和含有氟化苯三唑聚合物给体组成的有机光伏器件的优异光伏性能(光电转换效率大于13%),借助深入的量子化学计算,研究了氟化苯三唑聚合物给体、十环熔合非富勒烯受体及其异质结界面模型面-面相向构型复合物的几何结构、分子轨道、激发特性、分子表面静电势、转移电量和电荷转移距离.结果表明,氟化苯三唑聚合物给体:十环熔合非富勒烯受体异质结的卓越光伏性能是由于十环熔合非富勒烯受体分子内给体和受体片段之间的共面性,氟化苯三唑聚合物给体和十环熔合非富勒烯受体的电荷转移和杂化激发,在可见区域的互补光学吸收,以及从氟化苯三唑聚合物给体到十环熔合非富勒烯受体的分子表面静电势差值较大引起的.氟化苯三唑聚合物给体/十环熔合非富勒烯受体复合物的电子结构和激发表明,激子解离可以通过基于空穴转移的受体局域激发的衰退来实现,这不同于基于富勒烯受体的有机光伏的激子解离机理.通过Marcus理论评估的激子解离、电荷复合和电荷转移过程的速率常数表明有效的激子解离也是良好光伏性能的原因.Understanding organic photovoltaic(OPV)work principles and the materials’optoelectronic properties is fundamental for developing novel heterojunction materials with the aim of improving power conversion effi-ciency(PCE)of organic solar cells.Here,in order to understand the PCE performance(>13%)of OPV device composed of the non-fullerene acceptor fusing naphtho[1,2-b:5,6-b′]dithiophene with two thieno[3,2-b]thiophene(IDCIC)and the polymer donor fluorobenzotriazole(FTAZ),with the aid of extensive quantum chemistry calculations,we investigated the geometries,molecular orbitals,excitations,electrostatic potentials,transferred charges and charge transfer distances of FTAZ,IDCIC and their complexes with faceon configurations,which was constructed as heterojunction interface model.The results indicate that,the prominent OPV performance of FTAZ:IDCIC heterojunction is caused by co-planarity between the donor and acceptor fragments in IDCIC,the the charge transfer(CT)and hybrid excitations of FTAZ and IDCIC,the complementary optical absorptions in visible region,and the large electrostatic potential difference between FTAZ and IDCIC.The electronic structures and excitations of FTAZ/IDCIC complexes suggest that exciton dissociation can fulfill through the decay of local excitation exciton in acceptor by means of hole transfer,which is quite different from the OPVs based on fullerenes acceptor.The rates of exciton dissociation,charge recombination and CT processes,which were evaluated by Marcus theory,support the efficient exciton dissociation that is also responsible for good photovoltaic performance.

关 键 词：电子结构 激发 电荷转移 有机光伏 异质结界面 

分 类 号：TQ317[化学工程—高聚物工业] TM914.4[电气工程—电力电子与电力传动]