侧基可脱除共轭聚合物的合成及其在光电探测器中的应用  

Synthesis of Side-group Removable Conjugated Polymers and Their Applications in Photodetectors

作　　者：孙苗莘 闫显文 王鑫[1] 乔文强 王植源 Miao-shen Sun;Xian-wen Yan;Xin Wang;Wen-qiang Qiao;Zhi-yuanWang(State Key Laboratory of Fine Chemicals,Department of Polymer Science&Materials,Dalian University of Technology,Dalian 116024)

机构地区：[1]大连理工大学高分子材料系精细化工国家重点实验室,大连116024

出　　处：《高分子学报》2022年第11期1341-1348,共8页Acta Polymerica Sinica

基　　金：中央高校基本科研业务费(项目号DUT20RC(5)007)资助.

摘　　要：通过在吡咯并吡咯二酮(DPP)中引入热可脱去的叔丁氧羰基(Boc)基团,合成了一种新型的给-受体共轭聚合物P1.聚合物P1的溶解性研究表明,其在常见的有机溶剂(如四氢呋喃、甲苯、氯仿等)中均具有良好的溶解性,可进行溶液加工.热失重及红外光谱研究表明,P1可在适当的温度下退火实现Boc基团的脱除,形成不可溶聚合物P2.聚合物P1薄膜的最大吸收波长为829 nm,最高占据分子轨道(HOMO)能级与最低未占分子轨道(LUMO)能级分别为-5.25和-3.62 eV,将其作为活性层制备的光电探测器最大归一化探测率为8.20×10^(11) Jones.聚合物P2薄膜的最大吸收波长为771 nm,HOMO能级与LUMO能级分别为-5.30和-3.54 eV,将其作为空穴传输层制备的光电探测器暗电流密度为3.84×10^(-9) A/cm^(2),最大归一化探测率为3.96×10^(12) Jones.研究结果为共轭聚合物分子的结构设计与光电探测器性能的改善提供了新的思路.Donor-acceptor conjugated polymer P1 was synthesized by introducing a thermally removable tertbutoxycarbonyl(Boc)group into diketopyrrolopyrrole(DPP).The solubility study of polymer P1 shows that it has good solubility in common organic solvents(such as tetrahydrofuran,toluene,chloroform,etc.),and can be processed in solution.Thermogravimetric analysis and infrared spectroscopy show that the Boc group of P1 can be removed at an appropriate temperature and the insoluble polymer P2 can be formed.The maximum absorption wavelength of the polymer P1 film is 829 nm,the highest occupied molecular orbital(HOMO)level and the lowest unoccupied molecular orbital(LUMO)level are-5.25 and-3.62 eV,respectively.The photodetector with P1/PC61BM as active layer exhibits a maximum specific detectivity of 8.20×10^(11) Jones and dark current density of 6.49×10^(-8) A/cm^(2) under-0.1 V bias.The maximum absorption wavelength of the polymer P2 film is 771 nm,the HOMO and LUMO levels are-5.30 and-3.54 eV respectively.The dark current density of the photodetector with P2 as hole transport layer and P3HT/PC61BM as active layer is 3.84×10^(-9) A/cm^(2),and the maximum specific detectivity is 3.96×10^(12) Jones under-0.1 V bias.Compared with the device without hole transport layer and the device with PEDOT:PSS as hole transport layer,the device with P2 as hole transport layer shows lower dark current density and higher maximum specific detectivity.The results imply that polymer P2 with insoluble property is a potential candidate for hole transport material.This work provides new ideas for the selection of hole transport layer materials,the structural design of conjugated polymer molecules and the improvement of photodetector performance.

关 键 词：叔丁氧羰基(Boc) 共轭聚合物 溶解性 热退火 光电探测器 

分 类 号：TN15[电子电信—物理电子学] TQ317[化学工程—高聚物工业]