【作者】 王坤；

【导师】 付强； 李永舫；

【作者基本信息】 东北师范大学 ， 物理化学， 2013， 博士

【摘要】 高效给体聚合物光伏材料应具备吸收宽、电子能级与受体匹配、溶解性好、易形成纳米聚集结构等特点。基于以上考虑，本论文从更多高效、易合成受体单元的开发出发，设计合成了一系列基于新型受体单元的D-A型给体聚合物光伏材料，主要包括：(1)开发了一系列基于双F取代的二苯并吩嗪受体单元、BDT给体单元的D-A共聚物，对其光、电性能、光伏特性进行了表征。发现噻吩π桥上烷基链的取向会影响聚合物间的相互作用，进而影响到光伏性能。其中，P3与PC70BM以1:1共混时光电转换效率最高，为1.21%，比同样条件下的P1高46％。同时也证明了二维共轭能有效拓宽吸收光谱，提高器件的光伏性能。(2)合成了一种以双F取代的苯并三氮唑为受体单元，以IDT为给体单元的中带隙共轭聚合物PIDT-FBTA，强吸电子原子F的引入降低了PIDT-FBTA的HOMO能级，从而将器件的开路电压提高到0.90V，PCE达到3.62％。经极性甲醇处理后，器件整体性能提高了35％，PCE达到4.90％，Voc由0.90V提高到了0.92V，Jsc由7.68mAcm2提高到了9.60mAcm2，FF由0.52提高到了0.55。(3)开发了一种以噻吩/烷基噻吩为侧链的喹喔啉受体单元，并成功将其用于有机薄膜太阳能电池中。wk-6:PC70BM以质量比1:2.5共混时，120度退火后PCE达到3.15％，Voc为0.82V，Jsc为10.09mAcm2，FF为0.38。甲醇处理后，器件整体性能提高了23.8％，PCE达到3.90％，Voc由0.82V提高到了0.83V，Jsc由10.09mAcm2提高到了11.7mAcm2，FF由0.38提高到了0.40。然而，较低的FF表明wk-6有更多的潜力值得去挖掘，有望被开发成为一种高效的光伏材料。(4)开发了两类给、受体单元间噻吩π桥上带吸电子侧链的共轭聚合物，并初步探讨了吸电子基对聚合物的吸收光谱、热稳定性、电化学性能的影响。发现，在不影响聚合物骨架共平面性的前提下，π桥侧链吸电子基的引入能够降低聚合物的HOMO、LUMO能级，降低聚合物的带隙。这或许能为我们合成窄带隙聚合物提供一种方法。更多还原

【Abstract】 Wide absorption, electron energy level matching with acceptor, good solubility, easy toform nanomorphology are the prerequisite for efficient conjugated polymer donor materials.Based upon the consideration, this dissertation is focusing on the development and synthesisof new D-A copolymers based on new acceptor unit with the characteristics of facile synthesis.The main results are as follows:(1) A series of conjugated D-π-A copolymers, based on11,12-difluorodibenzo[a,c]phenazine (DFDBPz) as acceptor unit, benzodithiophene (BDT) asdonor unit, were development and synthesized. It was found that the orientation alkyl sidechain on the thiophene-bridge affected the intermolecular π-π interaction of the conjugatedpolymers. The optimum performance of the devices is obtained at1:1weight ratio ofP3:PC70BM with PCE of1.21%, which is46%higher than that of P1-based PSCs.(2) A medium band gap copolymer PIDT-FBTA based on FBTA and IDT wassynthesized and applied as donor material in PSCs. A higher Vocwas achieved, which isbenefitted from the deeper HOMO of PIDT-FBTA. The device based onPIDT-FBTA:PC70BM with1:3weight ratio displayed enhanced PCE of3.62%. Aftermethanol treatment, a significant35%enhancement in PCE (up to4.9%) with a simultaneousimprovement in Voc(0.90V to0.92V), Jsc(7.68mA cm2to9.60mA cm2) and FF (0.52to0.55) was achieved.(3) A new D-A copolymer based on thiophene substituent on quinoxaline acceptor unitwere developed and synthesized. The device based on wk-6:PC70BM with1:2.5weight ratiodisplayed a PCE of3.15%after thermal annealing at120oC. After methanol treatment, asignificant23.8%enhancement in PCE (up to3.90%) with a simultaneous improvement inVoc(0.82V to0.83V), Jsc(10.09mA cm2to11.7mA cm2) and FF (0.38to0.40) wasachieved.(4) Two kinds of new D-A copolymers based on DTBT with an electron-withdrawinggroup on thiophene bridge were developed and synthesized. The influence of electron-withdrawing group on thermal stability, optical absorption and the electrochemicalperformance were preliminary discussed. It was found that the HOMO/LUMO energy levelsand the band gap of the copolymers could be reduced by introducing electron-withdrawinggroup on thiophene bridge of without affecting copolymer skeleton coplanar. This mayprovide a method for synthesis of narrow band gap copolymers.更多还原