Charge Separation in a Nonfluorescent Donor−Acceptor Dyad Derived from Boron Dipyrromethene Dye, Leading to Photocurrent Generation

• Published in: The journal of physical chemistry. B Vol. 109; no. 32; pp. 15368 - 15375
• Main Authors: Hattori, Shigeki, Ohkubo, Kei, Urano, Yasuteru, Sunahara, Hisato, Nagano, Tetsuo, Wada, Yuji, Tkachenko, Nikolai V, Lemmetyinen, Helge, Fukuzumi, Shunichi
• Format: Journal Article
• Language: English
• Published: United States American Chemical Society 18.08.2005
• Subjects: Boron - chemistry; Coloring Agents - chemistry; Electrochemistry; Electrons; Ions - chemistry; Molecular Structure; Oxidation-Reduction; Photochemistry; Porphobilinogen - analogs & derivatives; Porphobilinogen - chemistry; Spectrophotometry
• ISSN: 1520-6106; 1520-5207
• DOI: 10.1021/jp050952x

Boron dipyrromethene (BODIPY), which is commonly used as an energy absorbing and transferring antenna molecule, has been modified to contain an electron donor moiety, 8-(2,4,5-trimethoxyphenyl)-4,4-difluoro-1,3,5,7-tetramethyl-4-bora-3a,4a-diaza-s-indacene (MEOPHBDP). The photoinduced electron transfer from a 2,4,5-trimethoxyphenyl moiety to a BODIPY moiety of MEOPHBDP in acetonitrile was observed by femtosecond laser flash photolysis measurements. The lifetime of the charge-separated state of MEOPHBDP was 59 ps at 298 K. The dye-sensitized solar cells (DSSC) were prepared using MEOPHBDP with carboxylic acid (MEOPHBDP−COOH) and a reference BODIPY dye having no electron donor moiety. The photovoltaic measurements were performed using a standard two-electrode system consisting of a working electrode and a Pt sputtered electrode in methoxyacetonitrile containing 0.5 M iodide and 0.05 M I2. The photoelectrochemical properties of DSSC with MEOPHBDP are compared with those with a reference BODIPY dye.