Park Eun Young, Jung Jaewook, Nam So Youn, Kim Pan Seok, Lee Jun Young, Lee Jaemin, Shin Won Suk, Moon Sang-Jin, Lee Changjin, Yoon Sung Cheol
Advanced Materials Division, Korea Research Institute of Chemical Technology (KRICT), Deajeon 305-600, South Korea.
J Nanosci Nanotechnol. 2012 May;12(5):4256-60. doi: 10.1166/jnn.2012.5932.
We report the PCDTBT {Poly[N-9'-heptadecanyl-2,7-carbazole-alt-5,5-(4',7'-di-2-thienyl-2',1',3'-benzothiadiazole)]}, an alternating copolymer of 2,7-carbazole and dithienyl-2,1,3-benzothiazole, has high molecular weight and narrow molecular weight distribution. Our PCDTBT can be successfully prepared as good yield by using tetrakis(triphenylphosphine)palladium [Pd(PPh3)4] catalyst instead of Pd2dba3/P(o-Tol)3 catalyst. From the UV/Vis absorption spectroscopy, we can observe that absorption bands of PCDTBT are bathochromically shifted by increasing the molecular weight, that is to say, our high molecular weight PCDTBT can absorb much longer wavelength light compare to low molecular weight PCDTBT. The best performance can be obtained from device based on the mixture of PCDTBT (polymer-30) and PC70BM {[6,6]-phenyl C71-butyric acid methyl ester} (1:4) as an active layer, which shows 4.50% of PCE with 10.1 mA/cm2 of short-circuit current density (J(SC)), 0.85 V of open-circuit voltage (V(OC)), and 52.3% of fill factor which is very similar with Leclerc's published result.
我们报道了聚[N-9'-十七烷基-2,7-咔唑-alt-5,5-(4',7'-二-2-噻吩基-2',1',3'-苯并噻二唑)]（PCDTBT），一种由2,7-咔唑和二噻吩基-2,1,3-苯并噻唑组成的交替共聚物，具有高分子量和窄分子量分布。通过使用四(三苯基膦)钯[Pd(PPh3)4]催化剂而非Pd2dba3/P(o-Tol)3催化剂，我们的PCDTBT能够以良好的产率成功制备。从紫外可见吸收光谱中，我们可以观察到PCDTBT的吸收带随着分子量的增加而发生红移，也就是说，与低分子量的PCDTBT相比，我们的高分子量PCDTBT能够吸收波长更长的光。基于PCDTBT（聚合物-30）和PC70BM{[6,6]-苯基-C71-丁酸甲酯}（1:4）的混合物作为活性层的器件表现出最佳性能，其短路电流密度（J(SC)）为10.1 mA/cm2，开路电压（V(OC)）为0.85 V，填充因子为52.3%，光电转换效率为4.50%，这与勒克莱尔发表的结果非常相似。
