1334686-71-3Relevant academic research and scientific papers
Correlation of structure and photovoltaic performance of benzo[1,2-b:4,5-b′]dithiophene copolymers alternating with different acceptors
Yu, Jiangsheng,Zhao, Baofeng,Nie, Xuemei,Zhou, Baojin,Li, Yang,Hai, Jiefeng,Zhu, Enwei,Bian, Linyi,Wu, Hongbin,Tang, Weihua
, p. 2248 - 2255 (2015/03/18)
Four π-conjugated benzo[1,2-b:4,5-b′]dithiophene (BDT) based polymers were synthesized for application in polymer solar cells. These polymers possessed desirable HOMO/LUMO levels for polymer photovoltaic applications. PBDTT-TTz and PBDTT-DTBT displayed strong absorption in the range of 300-650 nm, while PBDTT-DPP and PBDTT-TTDPP showed a further 100 nm extended absorption band. The lowest unoccupied molecular orbital energy levels of polymers were tuned effectively from -3.34 eV to -3.81 eV by fusing with different accepting units. A maximum power conversion efficiency of 2.60% was obtained from photovoltaic cells with a PBDTT-TTz:PC61BM (1:2, w/w) blend film as the active layer, with a short circuit current density of 8.37 mA cm-2, an open circuit voltage of 0.70 V, and a fill factor of 44.3%. This journal is
Comparison of thiophene- and selenophene-bridged donor-acceptor low band-gap copolymers used in bulk-heterojunction organic photovoltaics
Chen, Hung-Yang,Yeh, Shih-Chieh,Chen, Chao-Tsen,Chen, Chin-Ti
, p. 21549 - 21559 (2013/01/15)
We report a detailed comparison of absorption spectroscopy, electrochemistry, DFT calculations, field-effect charge mobility, as well as organic photovoltaic characteristics between thiophene- and selenophene-bridged donor-acceptor low-band-gap copolymers. In these copolymers, a significant reduction of the band-gap energy was observed for selenophene-bridged copolymers by UV-visible absorption spectroscopy and cyclic voltammetry. Field-effect charge mobility studies reveal that the enhanced hole mobility of the selenophene-bridged copolymers hinges on the solubilising alkyl side chain of the copolymers. Both cyclic voltammetry experiments and theoretical calculations showed that the decreased band-gap energy is mainly due to the lowering of the LUMO energy level, and the raising of the HOMO energy level is just a secondary cause. These results are reflected in a significant increase of the short circuit current density (JSC) but a slight decrease of the open circuit voltage (VOC) of their bulk-heterojunction organic photovoltaics (BHJ OPVs), of which the electron donor materials are a selenophene-bridged donor-acceptor copolymer: poly{9-dodecyl-9H-carbazole-alt-5, 6-bis(dodecyloxy)-4,7-di(selenophen-2-yl) benzo[c][1,2,5]-thiadiazole} (pCzSe) or poly{4,8-bis(2-ethylhexyloxy)benzo[1,2-b;4,5-b′]dithiophene-alt-5,6- bis(dodecyloxy)-4,7-di(selenophen-2-yl)benzo[c][1,2,5]-thiadiazole} (pBDTSe), or a thiophene-bridged donor-acceptor copolymer: poly{9-dodecyl-9H-carbazole-alt- 5,6-bis(dodecyloxy)-4,7-di(thiophen-2-yl)benzo[c][1,2,5]-thiadiazole} (pCzS) or poly{4,8-bis(2-ethylhexyloxy)benzo[1,2-b;4,5-b′]dithiophene-alt-5, 6-bis(dodecyloxy)-4,7-di(thiophen-2-yl)benzo[c][1,2,5]-thiadiazole} (pBDTS); the electron acceptor material is [6,6]-phenyl-C61-butyric acid methyl ester (PCBM). Judging from our device data, the potential Se-Se interactions of the selenophene-bridged donor-acceptor copolymers, which is presumably beneficial for the fill factor (FF) of BHJ OPVs, is rather susceptible to the device fabrication conditions.
New moderate bandgap polymers containing alkoxysubstituted-benzo[c][1,2,5] thiadiazole and thiophene-based units
Lim, Zheng Bang,Xue, Bofei,Bomma, Swarnalatha,Li, Hairong,Sun, Shuangyong,Lam, Yeng Ming,Belcher, Warwick J.,Dastoor, Paul C.,Grimsdale, Andrew C.
, p. 4387 - 4397 (2012/05/20)
Alkoxysubstituted benzo[c][1,2,5]thiadiazole electron accepting units were prepared and copolymerized with various thiophene-based electron donating monomers to produce new low bandgap polymers P1-4. The materials showed broad absorption in the range from
