1194605-76-9Relevant academic research and scientific papers
Highly Stable Polymer Solar Cells Based on Poly(dithienobenzodithiophene- co -thienothiophene)
Shin, Nara,Yun, Hui-Jun,Yoon, Youngwoon,Son, Hae Jung,Ju, Sang-Yong,Kwon, Soon-Ki,Kim, Bongsoo,Kim, Yun-Hi
, p. 3890 - 3899 (2015)
It is important to develop new donor (D)-acceptor (A) type low band gap polymers for highly stable polymer solar cells (PSCs). Here, we describe the synthesis and photovoltaic properties of two D-A type low band gap polymers. The polymers consist of dithienobenzodithiophene (DTBDT) moieties with expanded conjugation side groups as donors and 2-ethyl-1-(thieno[3,4-b]thiophen-2-yl)hexan-1-one (TTEH) or 6-octyl-5H-thieno[3′,4′:4,5]thieno[2,3-c]pyrrole-5,7(6H)-dione (DTPD) as acceptors to give pDTBDT-TTEH and pDTBDT-DTPD polymers, respectively. The pDTBDT-TTEH is quite flat, resulting in a highly crystalline film. In contrast, the pDTBDT-DTPD is highly twisted to yield an amorphous film. Photovoltaic devices based on pDTBDT-TTEH and pDTBDT-DTPD exhibited power conversion efficiencies (PCEs) of 6.74% and 4.44%, respectively. The PCE difference results mainly from morphological differences between the two polymer:PC71BM blend films; the pDTBDT-TTEH polymer formed a nanoscopically networked domains in the blend state, while the pDTBDT-DTPD polymer film contained aggregated domains with large phase separation between the polymer and PC71BM molecules. Importantly, we observed that pDTBDT-TTEH-based devices showed excellent stability-in air, retaining 95% of the initial PCE after storage for over 1000 h without encapsulation. The high stability of the pDTBDT-TTEH-based device was originated mainly by the crystalline nature of the pDTBDT-TTEH:PC71BM film. This work suggests that designing highly conjugated planar backboned polymers is crucial to improve not only the photovoltaic performance but also the stability of PSCs.
Design, synthesis and photophysical properties of A-D-A-D-A small molecules for photovoltaic application
Yan, Weibo,Zhang, Qian,Qin, Qingsong,Ye, Senyun,Lin, Yuanwei,Liu, Zhiwei,Bian, Zuqiang,Chen, Yongsheng,Huang, Chunhui
, p. 99 - 108 (2015/06/08)
A series of linear-conjugated small molecule compounds featured with the acceptor-donor-acceptor-donor-acceptor (A-D-A-D-A) structure were designed, synthesized and characterized. The films of the compounds showed a broad UV-Vis absorption range of 300-800 nm with high molar absorption coefficient of more than 1.0 × 104 cm-1. Their hole-mobility can be as high as 1.0 × 10-3 cm2 V-1 s-1. The compounds have a compatible HOMO energy level of -5.0 eV to PC71BM and a high solubility up to 20 mg mL-1 in chloroform. Therefore, compounds can blend with PC71BM in the chloroform and form an active layer for a photovoltaic cell device by spin-coating of the blend solution. A maximum power conversion efficiency of 3.2% was achieved with the DERH3TT solar cell device. These results indicate that the A-D-A-D-A small molecules with electron-withdrawing dyes as terminals are promising candidates for the high efficiency solution processed organic photovoltaic cells.
Synthesis of a low band gap polymer and its application in highly efficient polymer solar cells
Hou, Jianhui,Chen, Hsiang-Yu,Zhang, Shaoqing,Chen, Ruby I.,Yang, Yang,Wu, Yue,Li, Gang
supporting information; experimental part, p. 15586 - 15587 (2010/01/29)
(Chemical Equation Presented) HOMO level of the PBDTTT-based polymer was successfully reduced by introducing an keton group in place of the ester group. The average PCE of the PBDTTT-based devices reached 6.3% with a champion PCE result of 6.58%. Due to i
