基于吡咯并吡咯二酮的二元和三元共轭聚合物的光电性能研究  

Photovoltaic Properties of DPP-based Two-and Three-component Polymers

作　　者：章中强 刘志玺 严康荣 李焕斌 刘文清 路新慧 李寒莹[1] 陈红征[1] 李昌治 

机构地区：[1]浙江大学高分子科学与工程学系硅材料国家重点实验室,杭州310027 [2]香港中文大学物理系

出　　处：《高分子学报》2018年第2期295-303,共9页Acta Polymerica Sinica

基　　金：国家自然科学基金(基金号21674093;51620105006);国家自然科学基金优秀青年科学基金(基金号21722404);国家重点基础研究发展计划(973计划;项目号2014CB643503);科技部国际科技合作项目(项目号2016YFE0102900);浙江省自然科学基金杰出青年科学基金(基金号LR17E030001)资助项目

摘　　要：设计合成了基于吡咯[3,4-c]并吡咯二酮(DPP)和烷氧基苯的二元共轭聚合物P1,并通过聚合中分别引入缺电子性第三单体二氟代苯并噻二唑(DFBT)和萘二酰亚胺(NDI),进一步得到三元聚合物P2和P3.结果显示,缺电子第三单体的设计引入能调节聚合物的吸光、能级并改变聚合物在薄膜状态下的聚集行为,从而影响材料的聚合物太阳能电池光电转换效率和有机场效应晶体管电荷迁移率,采取face-on聚集取向的P1在太阳电池中表现更好,而edge-on取向的P2则在晶体管中表现出更高的空穴迁移率.Diketopyrrolopyrrole（DPP） is attractive for building conjugated polymers for polymer solar cell（PSC） and organic field effect transistor（OFET）.Yet the usual access to DPP conjugated polymers is via donor-acceptor（D-A） two-component polymerization.However,the number of excellent polymers based on the D-A combination is still limited,which promotes researchers to explore new strategy for preparation of novel conjugated polymers and to understand their structure-property relationship.In this work,a DPP-based polymer P1 was first obtained with co-polymerization of DPP（A） and alkoxyl benzene（D）.Further,two novel polymers（P2 and P3） were developed via introducing a third electron-deficient monomer X（difluoro-benzothiadiazole or naphthalene diimide） in the polymerization process.P1-P3 polymers（molecular weight： 3.83 ′ 104,5.30 ′ 104 and 6.56 ′104） showed good solubility in common organic solvents.Due to the hybridization of the molecular orbitals between their three components（D,A and X）,P2 and P3 showed narrower bandgaps（1.26 and 1.27 eV） than P1,and their absorption thus red-shifted up to 1000 nm in comparison to that of D-A polymer P1（bandgap of 1.50 eV）.The introduction of electron-deficient monomers also deepened the highest occupied molecular orbital（HOMO） levels of P2 and P3 to -5.28 and-5.33 eV,which was beneficial to a larger open circuit voltage（VOC） in PSCs.Moreover,the introduction of the third monomer X altered the film properties of the polymers.It showed that P1 with preference of face-on orientation exhibited a good power conversion efficiency（PCE） in PSCs,while P2 demonstrated an improved hole mobility in OFET due to the preferable edge-on orientation.When blended with [6,6]-phenyl-C71-butyric acid methyl ester（PC71 BM）,P1 showed a PCE of 2.56%,with a VOC of 0.68 V,a short circuit current density（JSC） of 5.71 mA cm^-2 and a fill factor（FF） of 0.66,while P2 gave a lower PCE of 1.79%,with a VOC of 0.71 V,a JSC of 3.91 mA cm^-2

关 键 词：聚合物太阳能电池 共聚 吡咯并吡咯二酮 缺电子单元 

分 类 号：TM914.4[电气工程—电力电子与电力传动]