TY - JOUR
T1 - Dithienosilole-bridged small molecules with different alkyl group substituents for organic solar cells exhibiting high open-circuit voltage
AU - Ye, Dandan
AU - Li, Xiaodong
AU - Yan, Lei
AU - Zhang, Wenjun
AU - Hu, Zhao
AU - Liang, Ying
AU - Fang, Junfeng
AU - WONG, Wai Yeung
AU - Wang, Xingzhu
N1 - This work was financially supported by the National Natural Science Foundation of China (no. 51273208, 20974091 and 50803051), the Hundred Talent Program of Chinese Academy of Sciences, the Starting Research Fund of Team Talent (Y10801RA01) in NIMTE and the Ningbo Natural Science Foundation of China (2012A610114), Natural Science Foundation of Hunan Province of China (no. 10JJ1002), the Foundation of the Hunan Provincial Education Department (10B107) and the Undergraduate Innovation Experiment Plan in the Xiangtan University. W.-Y. W. thanks the Hong Kong Baptist University (FRG2/12-13/083), and Hong Kong Research Grants Council (HKBU203011). The work described in this paper was also partially supported by a grant from the Research Grants Council of the Hong Kong Special Administrative Region, China (project no. [T23-713/11]).
PY - 2013
Y1 - 2013
N2 - Three new small organic molecules, I, II and III, consisting of dithienosilole as the central core, bithiophene bridge with different alkyl group substituents, and octyl cyanoacetate or dicyano unit as different end units, have been designed and synthesized. The thermal, optical, electrochemical and photovoltaic properties of these three compounds have been investigated. The solubility, absorption, energy levels and band gaps of these materials were effectively tuned by different alkyl groups substituted on the thiophene unit and/or different electron-withdrawing end groups. Bulk heterojunction solar cells with molecules I-III as electron donors and PC60BM ([6,6]-phenyl-C60-butyric acid methyl ester) as an election acceptor exhibited power conversion efficiencies of 3.27, 2.88 and 3.81% for I, II and III, respectively. All of these solar cells showed very high Voc values of 0.89-0.92 V, and the high Voc is consistent with the low-lying HOMO level of the donor. These compounds also have low LUMO levels which ensure effective charge transfer from the donor to the fullerene acceptor. The structure-photovoltaic property relationships of these donor materials were investigated and discussed.
AB - Three new small organic molecules, I, II and III, consisting of dithienosilole as the central core, bithiophene bridge with different alkyl group substituents, and octyl cyanoacetate or dicyano unit as different end units, have been designed and synthesized. The thermal, optical, electrochemical and photovoltaic properties of these three compounds have been investigated. The solubility, absorption, energy levels and band gaps of these materials were effectively tuned by different alkyl groups substituted on the thiophene unit and/or different electron-withdrawing end groups. Bulk heterojunction solar cells with molecules I-III as electron donors and PC60BM ([6,6]-phenyl-C60-butyric acid methyl ester) as an election acceptor exhibited power conversion efficiencies of 3.27, 2.88 and 3.81% for I, II and III, respectively. All of these solar cells showed very high Voc values of 0.89-0.92 V, and the high Voc is consistent with the low-lying HOMO level of the donor. These compounds also have low LUMO levels which ensure effective charge transfer from the donor to the fullerene acceptor. The structure-photovoltaic property relationships of these donor materials were investigated and discussed.
UR - http://www.scopus.com/inward/record.url?scp=84880075793&partnerID=8YFLogxK
U2 - 10.1039/c3ta11257h
DO - 10.1039/c3ta11257h
M3 - Journal article
AN - SCOPUS:84880075793
SN - 2050-7488
VL - 1
SP - 7622
EP - 7629
JO - Journal of Materials Chemistry A
JF - Journal of Materials Chemistry A
IS - 26
ER -