title: Dipolar compounds containing fluorene and a heteroaromatic ring as the conjugating bridge for high-performance dye-sensitized solar cells.
abstract: A novel series of dipolar organic dyes containing diarylamine as the electron donor, 2-cyanoacrylic acid as the electron acceptor, and fluorene and a heteroaromatic ring as the conjugating bridge have been developed and characterized. These metal-free dyes exhibited very high molar extinction coefficients in the electronic absorption spectra and have been successfully fabricated as efficient nanocrystalline TiO(2) dye-sensitized solar cells (DSSCs). The solar-energy-to-electricity conversion efficiencies of DSSCs ranged from 4.92 to 6.88%, which reached 68-96% of a standard device of N719 fabricated and measured under the same conditions. With a TiO(2) film thickness of 6 microm, DSSCs based on these dyes had photocurrents surpassing that of the N719-based device. DFT computation results on these dyes also provide detailed structural information in connection with their high cell performance.
authors.affiliation: Institute of Chemistry, Academia Sinica, Taipei, 115, Taiwan.
authors.forename: Chih-Hsin
authors.initials: CH
authors.lastname: Chen
authors.forename: Ying-Chan
authors.initials: YC
authors.lastname: Hsu
authors.forename: Hsien-Hsin
authors.initials: HH
authors.lastname: Chou
authors.forename: K R Justin
authors.initials: KR
authors.lastname: Thomas
authors.forename: Jiann T
authors.initials: JT
authors.lastname: Lin
authors.forename: Chao-Ping
authors.initials: CP
authors.lastname: Hsu