Abstract

A series of new random terpolymers was synthesized by copolymerization of one electron-donor alkyl-substituted benzodithiophene unit and two electron-acceptor units, diketopyrrolopyrrole (DPP) and bis(4,5-dodecylthiophen-2-yl)-[1,2,5]thiadiazol[3,4-i]dithieno[3,2-a:2',3'-c]phenazine (DF). The influence of the DPP/DF ratio on the thermal, optoelectronic, and electrochemical properties of the terpolymers was investigated using thermogravimetric analysis, UV-Vis spectroscopy, and cyclic voltammetry. The optical properties of the synthesized terpolymers were controlled by varying the DPP/DF ratio. An increase in the DF mole fraction in the polymer chain caused an increase in absorption intensity in the 300‒600 and 600‒1100 nm ranges, while increasing mole fraction of DPP resulted in stronger absorption in the 600‒900 nm range and lower absorption intensity in the 350‒600 nm range. The terpolymers exhibited broad and intense absorption over the spectral range from 300 to 1100 nm. The results demonstrate that random terpolymers with complementary absorption spectra have a great potential for increasing the photocurrent and efficiency of polymer solar cells.

中文翻译：

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基于双（4,5-二十二烷基噻吩-2-基）-[1,2,5]噻二唑并[3,4-i]二噻吩并[3,2-a：2'，3'-c]吩嗪的新型无规三元共聚物具有可变吸收光谱的有机太阳能电池有望材料

摘要

通过一个电子供体烷基取代的苯并二噻吩单元和两个电子受体单元，二酮吡咯并吡咯（DPP）和双（4,5-十二烷基噻吩-2-基）-[1,2， 5] thiadiazol [3,4- i ] dithieno [3,2- a：2'，3'- c吩嗪（DF）。使用热重分析，UV-Vis光谱和循环伏安法研究了DPP / DF比对三元共聚物的热，光电和电化学性质的影响。通过改变DPP / DF比率来控制合成三元共聚物的光学性质。聚合物链中DF摩尔分数的增加导致300‒600和600‒1100 nm范围内的吸收强度增加，而DPP摩尔分数的增加导致600‒900 nm范围内更强的吸收和较低的吸收强度在350‒600 nm范围内。三元共聚物在300至1100 nm的光谱范围内表现出广泛而强烈的吸收。