Molecular Level Factors Affecting the Efficiency of Organic Chromophores for p-Type Dye Sensitized Solar Cells

Energies

Svitlana Karamshuk²  Stefano Caramori¹  Norberto Manfredi²  Matteo Salamone²  Riccardo Ruffo²  Stefano Carli¹  Carlo A. Bignozzi¹  Alessandro Abbotto² 

[1]Department of Chemistry, University of Ferrara, Via L. Borsari 46, 44121 Ferrara, Italy

[2]Department of Materials Science and Milano-Bicocca Solar Energy Research Center—MIB-Solar, University of Milano-Bicocca, INSTM Unit, Via Cozzi 55, 20125 Milano, Italy

关键词: dyes;    heteroaromatic;    visible absorption;    dipolar;    donor–acceptor;    triphenylamine;    branched;    Suzuki coupling;    DFT-TDDFT;   

DOI  :  10.3390/en9010033

来源: mdpi

【 摘 要 】

A series of mono- and di-branched donor-π-acceptor charge-separated dyes incorporating triphenylamine as a donor and either Dalton’s or benzothiadiazole group as strong acceptors was synthesized and its fundamental properties relevant to the sensitization of nanocrystalline NiO investigated. The dyes exhibited an intense visible absorption band with a strong charge transfer character favorable to NiO sensitization, shifting the electron density from the donor to the acceptor branches. Nevertheless, the computed exciton binding energy is circa twice that of a common literature standard (P1), suggesting a more difficult charge separation. When tested in p-type dye-sensitized solar cells the dyes successfully sensitized NiO electrodes, with photocurrent densities about half than that of the reference compound. Being recombination kinetics comparable, the larger photocurrent generated by P1 agrees with the superior charge separation capability originating by its smaller exciton binding energy.

【 授权许可】

CC BY   
© 2016 by the authors; licensee MDPI, Basel, Switzerland.