Functionalization of a Ruthenium-Diacetylide Organometallic Complex as a Next-Generation Push-Pull Chromophore

• Published in: Chemistry : a European journal 2014-06, Vol.20 (23), p.7017-7024
• Main Authors: De Sousa, Samuel, Ducasse, Laurent, Kauffmann, Brice, Toupance, Thierry, Olivier, Céline
• Format: Article
• Language: English
• Subjects: Asymmetry; Chemistry; Chromophores; Devices; Dyes; electron transfer; Energy conversion efficiency; Metalorganic compounds; organometallic compounds; Photovoltaic cells; ruthenium; sensitizers; Solar cells; Solar energy
• ISSN: 0947-6539; 1521-3765
• DOI: 10.1002/chem.201304611

The design and preparation of an asymmetric ruthenium–diacetylide organometallic complex was successfully achieved to provide an original donor–π–[M]–π–acceptor architecture, in which [M] corresponds to the [Ru(dppe)2] (dppe: bisdiphenylphosphinoethane) metal fragment. The charge‐transfer processes occurring upon photoexcitation of the push–pull metal–dialkynyl σ complex were investigated by combining experimental and theoretical data. The novel push–pull complex, appropriately end capped with an anchoring carboxylic acid function, was further adsorbed onto a semiconducting metal oxide porous thin film to serve as a photosensitizer in hybrid solar cells. The resulting photoactive material, when embedded in dye‐sensitized solar cell devices, showed a good spectral response with a broad incident photon‐to‐current conversion efficiency profile and a power conversion efficiency that reached 7.3 %. Thus, this material paves the way to a new generation of organometallic chromophores for photovoltaic applications. The next generation: Asymmetric functionalization of a ruthenium–diacetylide organometallic complex afforded an innovative push–pull structure (see figure; D: donor; A: acceptor) with excellent optoelectronic properties and a good power conversion efficiency rate when it was employed as a photosensitizer in dye‐sensitized solar cells.