CAJ | 학술논문

本体异质结聚合物太阳电池的活性层通常是由聚合物给体和富勒烯受体通过机械混合而成，活性层的聚合物和富勒烯分子从热力学角度倾向于各自聚集，由此形成的纳米微相分离结构是热不稳定的，造成电池稳定性较差。为了提高活性层薄膜形貌稳定性，本文设计并合成出新型的溴基团取代的光交联型窄带隙聚合物PBDTTT-Br25和PBDTTT-Br50。经光引发交联后的聚合物薄膜表现出良好的抗溶剂性和形貌稳定性，且不影响聚合物分子排列及载流子传输性能。通过研究热退火对共混膜形貌的影响，发现使用光交联材料可以有效抑制富勒烯分子聚集，并提高聚合物太阳电池的热稳定性。基于PBDTTT-Br25和PBDTTT-Br50的器件光电转换效率分别为5．17％和4．48％，相比于基于聚合物PBDTTT的器件效率（4．26％），性能得到明显的提高。
본체이질결취합물태양전지적활성층통상시유취합물급체화부륵희수체통과궤계혼합이성，활성층적취합물화부륵희분자종열역학각도경향우각자취집，유차형성적납미미상분리결구시열불은정적，조성전지은정성교차。위료제고활성층박막형모은정성，본문설계병합성출신형적추기단취대적광교련형착대극취합물PBDTTT-Br25화PBDTTT-Br50。경광인발교련후적취합물박막표현출량호적항용제성화형모은정성，차불영향취합물분자배렬급재류자전수성능。통과연구열퇴화대공혼막형모적영향，발현사용광교련재료가이유효억제부륵희분자취집，병제고취합물태양전지적열은정성。기우PBDTTT-Br25화PBDTTT-Br50적기건광전전환효솔분별위5．17％화4．48％，상비우기우취합물PBDTTT적기건효솔（4．26％），성능득도명현적제고。
The active layer of bulk heteroj unction polymer solar cells is usually prepared by mechanical blending of polymer donors and fullerene acceptors.The polymer or fullerenes in the blend layer prefers to segregate from each other thermodynamically;therefore,the phase-separated nanostructure of the active layer is thermally unstable,which increases the instability of the PSCs. To stabilize the film morphology of the active layer,novel bromine-functionalized photocrosslinkable low-bandgap copolymers, PBDTTT-Br25 and PBDTTT-Br50 are designed and synthesized.The photo-crosslinked polymer films exhibit excellent solvent resistance and thermal morphology stability,and the photoinitiation process shows minimal effect on the packing of conj ugated polymers and electronic properties.The formation of large aggregations of fullerene is suppressed even after prolonged thermal annealing,and the stability of the device is enhanced.The power conversion efficiency of the PBDTTT-Br25-based and PBDTTT-Br50-based PSCs reaches 5.17%and 4.48%,respectively,which is much higher than that (4.26%)of the PBDTTT-based de-vice.