新型基于烷氧噻吩炔的共轭聚合物受体的设计、合成及光伏性能

Design, Synthesis and Photovoltaic Performance of Novel Conjugated Polymer Acceptors Based on Alkoxy Substituted Diethynylthiophene

设计合成了两个新型基于烷氧噻吩炔单元的共轭聚合物受体(PTO和NTO)。PTO和NTO的给体单元为烷氧基取代的噻吩,受体单元分别为苝二酰亚胺(PDI)和萘二酰亚胺(NDI),炔键作为连接桥键。两个共轭聚合物受体都具有较宽的吸收光谱和较浅的最低未占有轨道(LUMO)能级(>-3.80eV)。我们采用中等带隙的PBDB-T作为给体材料,PTO、NTO分别作为电子受体材料,制备了全聚合物太阳电池器件。基于NTO的电池器件可以获得3.7%的能量转化效率,高于基于PTO的电池器件效率(2.8%)。这主要是因为,基于NTO的电池器件具有更高的开路电压(V_(oc))和载流子迁移率。

Two novel conjugated polymer acceptors (PTO and NTO) were designed and synthesized.PTO and NTO possess alkoxy-substituted thiophene as electron donor moiety and ethynyl moiety as the π-bridge in the conjugated polymer backbone,while perylene diimide (PDI) or naphdiimide (NDI) moiety are used as electron acceptor moiety in their conjugated polymer backbones.Both PTO and NTO exhibited broad light-absorption spectra and low lowest unoccupied molecular orbital energy levels (>-3.80eV).All-polymer solar cells (all-PSCs) were fabricated using these copolymers as electron acceptors and a medium-bandgap conjugated polymer,PBDB-T,as the electron donor.The resulting all-PSCs based on NTO exhibited a power conversion efficiency of 3.7%,which is higher than that of the devices with PTO as acceptor (2.8%).The performance improvement was attributed to the higher open-circuit voltage,greater mobility of the PBDB-T:NTO based devices.