Alkyl-Functionalized Organic Dyes for Efficient Molecular Photovoltaics

• Published in: Journal of the American Chemical Society Vol. 128; no. 44; pp. 14256 - 14257
• Main Authors: Koumura, Nagatoshi, Wang, Zhong-Sheng, Mori, Shogo, Miyashita, Masanori, Suzuki, Eiji, Hara, Kohjiro
• Format: Journal Article
• Language: English
• Published: WASHINGTON American Chemical Society 08.11.2006; Amer Chemical Soc
• Subjects: Chemistry; Chemistry, Multidisciplinary; Exact sciences and technology; General and physical chemistry; Physical Sciences; Science & Technology; CONVERSION EFFICIENCY; SENSITIZED SOLAR-CELLS; DESIGN; FILMS; LIGHT; NANOCRYSTALLINE TIO2 ELECTRODES; COUMARIN DYES; Organic dye; Functionalization; Photovoltaic system
• ISSN: 0002-7863; 1520-5126
• DOI: 10.1021/ja0645640

We designed and synthesized new alkyl-functionalized organic dyes, MK-1 and MK-2, for dye-sensitized solar cells (DSSCs). Based on the MK-2 dye, a high performance of efficiency (η, 7.7%; short-circuit current density J sc = 14.0 mA cm-2, open-circuit voltage V oc = 0.74 V, and fill factor FF = 0.74) was achieved under AM 1.5 G irradiation (100 mW cm-2). Remarkably, the relatively higher V oc for DSSCs based on MK-1 and MK-2 dyes, which have long alkyl chains, were observed among the organic dyes caused by the increasing of the electron lifetime in the conduction band of TiO2. Our molecular design of alkyl-functionalized dyes strongly suggests the promising performance of molecular photovoltaics based on organic dyes.