Two structural isomers of the bisacrylonitrilethienothiophene–benzodithiophene copolymer, pBαCN and pBβCN, have been comprehensively studied by differential calorimetry, UV–visible absorption spectroscopy, cyclic voltammetry, density functional theory calculation, grazing incidence wide-angle X-ray scattering, transmission electron microscopy, fluorescence spectroscopy, and space-charge-limited current determination. We have obtained insightful information to elucidate why the β-isomer of the copolymer (pBβCN) can achieve a higher open-circuit voltage (0.96 V) along with a higher short-circuit current density (15.62 mA/cm²) and hence a higher power conversion efficiency of 9.27% than the α-isomer of the copolymer (pBαCN) in [6,6]-phenyl-C71-butyric acid methyl ester (PC₇₁BM)-blended bulk heterojunction polymer solar cells.

中文翻译：

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阐明基于二氰基取代的乙烯-噻吩并噻吩-乙烯-苯并二噻吩共聚物的聚合物太阳能电池的效率：β-异构体优于α-异构体

所述bisacrylonitrilethienothiophene-苯并二噻吩共聚物的两种结构异构体，pBαCN和pBβCN，已全面地由差示量热，紫外-可见吸收光谱法，循环伏安法，密度泛函理论计算，研究，掠入射广角X射线散射，透射电子显微镜，荧光光谱和空间电荷限制电流测定。我们已经获得了深刻的信息来阐明为什么共聚物 ( pBβCN )的 β-异构体可以实现更高的开路电压 (0.96 V) 以及更高的短路电流密度 (15.62 mA/cm ² )，从而获得更高的功率转换效率比共聚物的α-异构体（pBαCN）高9.27%) 在 [6,6]-苯基-C71-丁酸甲酯 (PC ₇₁ BM)-混合本体异质结聚合物太阳能电池中。