Three-dimensional tetra(oligothienyl)silanes as donor material for organic solar cells
作者:Sophie Roquet、R?mi de Bettignies、Philippe Leriche、Antonio Cravino、Jean Roncali
DOI:10.1039/b604261a
日期:——
Tetrahedral conjugated systems involving four conjugated oligothiophene chains fixed onto a central silicon node (1, 2) have been synthesized and used as donor materials in hetero-junction solar cells. Bilayer solar cells have been realized by thermal evaporation of compounds 1 and 2 as donors and N,N′-bis-tridecylperylenedicarboxyimide as an acceptor. Comparison of the performances of these devices to those of a reference system based on dihexylterthienyl (H3T) shows that despite comparable effective conjugation lengths, the 3D compounds 1 and 2 lead to a power conversion efficiency four–five times higher, suggesting better absorption of the incident light and better hole transport properties. Whereas fabrication of bulk hetero-junction with H3T was prevented by the lack of film forming properties, a prototype bulk hetero-junction based on compound 2 as the donor and [6,6]-phenyl-C61-butyric acid methyl ester (PCBM) as the acceptor has been realized. A short-circuit current density of 1.13 mA cm−2 and a power conversion efficiency of 0.30% has been measured under AM 1.5 simulated solar irradiation at 80 mW cm−2.
Syntheses of new oligothiophenes which have cyano and hexyl groups at the ends of quarter- and ter-thiophenes are described. The observations of DSC and polarizing microscopy indicate the presence of liquid-crystalline (LC) phases over a wide temperature range. The energy gaps are discussed on the basis of the absorption and photoluminescence (PL) spectra and cyclic voltammetry. Thin films of oligothiophenes fabricated by vacuum deposition are investigated by AFM and XRD measurements.
介绍了在四分之一噻吩和三噻吩末端带有氰基和己基的新型低聚噻吩的合成过程。DSC 和偏振显微镜的观察结果表明,在很宽的温度范围内都存在液晶(LC)相。根据吸收和光致发光(PL)光谱以及循环伏安法讨论了能隙问题。通过原子力显微镜 (AFM) 和 X 射线衍射 (XRD) 测量研究了通过真空沉积制造的低聚噻吩薄膜。
Byron, David; Matharu, Avtar; Wilson, Robert, Molecular Crystals and Liquid Crystals Science and Technology, Section A: Molecular Crystals and Liquid Crystals, 1995, vol. 265, p. 61 - 76
One-dimensional porphyrin H-aggregates induced by solvent polarity
作者:Myung-Seok Choi
DOI:10.1016/j.tetlet.2008.09.140
日期:2008.12
A series of new porphyrin derivatives possessing the side arms of alkyl-substituted thiophene oligomer were synthesized. The effects of solvent polarity on the formation of supramolecular assembly have been studied by UV-vis absorption, fluorescence emission, and TEM measurement. The linear-shape porphyrin derivatives bearing two thiophene pentamers at meso-position showed the significant spectral changes in both blue-shift and band broadening of Soret bands which indicate the formation of a relatively larger porphyrin H-aggregate that occurred in nonpolar solvent such as n-hexane. (c) 2008 Elsevier Ltd. All rights reserved.