Mapping the frontier electronic structures of triphenylamine based organic dyes at TiO2 interfaces.

The frontier electronic structures of a series of organic dye molecules containing a triphenylamine moiety, a thiophene moiety and a cyanoacrylic acid moiety have been investigated by photoelectron spectroscopy (PES), X-ray absorption spectroscopy (XAS), X-ray emission spectroscopy (XES) and resonant photoelectron spectroscopy (RPES). The experimental results were compared to electronic structure calculations on the molecules, which are used to confirm and enrich the assignment of the spectra. The approach allows us to experimentally measure and interpret the basic valence energy level structure in the dye, including the highest occupied energy level and how it depends on the interaction between the different units.

Distance and driving force dependencies of electron injection and recombination dynamics in organic dye-sensitized solar cells.

A series of dyes based on a triphenylamine donor and a rhodanine acetic acid anchor/acceptor for solar cell application has been studied with regards to electron injection and recombination kinetics using femtosecond transient absorption. The series contains three dyes, with estimated electron transfer distances ranging from 17.2 to 11.

Electronic and molecular structures of organic dye/TiO(2) interfaces for solar cell applications: a core level photoelectron spectroscopy study.

The electronic and molecular properties of three organic dye molecules with the general structure donor-linker-anchor have been investigated using core level photoelectron spectroscopy (PES). The molecules contain a diphenylaniline donor unit, a thiophene linker unit, and cyanoacrylic acid or rhodanine-3-acetic acid anchor units. They have been investigated both in the form of a multilayer and adsorbed onto nanoporous TiO(2) and the experimental results were also compared with DFT calculations.

How the nature of triphenylamine-polyene dyes in dye-sensitized solar cells affects the open-circuit voltage and electron lifetimes.

Three donor-linker-acceptor triphenylamine-based cyanoacrylic acid organic dyes used for dye-sensitized solar cells (DSCs) have been examined with respect to their effect on the open-circuit voltage (V(oc)). Our previous study showed a decrease in V(oc) for DSCs based on dyes with increased molecular size (increased linker conjugation). In the present study, we investigate the origin of V(oc) with respect to (i) conduction band (E(CB)) positions of TiO(2) and (ii) degree of recombination between electrons in TiO(2) and electrolyte acceptor species at the interface.

A light-resistant organic sensitizer for solar-cell applications.

Finely tuned: A stable dye-sensitized solar cell that contains a molecularly engineered organic dye has been prepared. The efficiency of the cell remains at 90% after 1000 h of light soaking at 60 degrees C. The remarkable stability of the cell is also reflected in the open-circuit voltage value (V(oc)), short-circuit photocurrent-density value (J(sc)), and the fill factor, which also show barely no decline (see picture).

Rhodanine dyes for dye-sensitized solar cells : spectroscopy, energy levels and photovoltaic performance.

Three new sensitizers for photoelectrochemical solar cells were synthesized consisting of a triphenylamine donor, a rhodanine-3-acetic acid acceptor and a polyene connection. The conjugation length was systematically increased, which resulted in two effects: first, it led to a red-shift of the optical absorption of the dyes, resulting in an improved spectral overlap with the solar spectrum. Secondly, the oxidation potential decreased systematically.

Molecular engineering of organic sensitizers for dye-sensitized solar cell applications.

Novel unsymmetrical organic sensitizers comprising donor, electron-conducting, and anchoring groups were engineered at a molecular level and synthesized for sensitization of mesoscopic titanium dioxide injection solar cells. The unsymmetrical organic sensitizers 3-(5-(4-(diphenylamino)styryl)thiophen-2-yl)-2-cyanoacrylic acid (D5), 3-(5-bis(4-(diphenylamino)styryl)thiophen-2-yl)-2-cyanoacrylic acid (D7), 5-(4-(bis(4-methoxyphenylamino)styryl)thiophen-2-yl)-2-cyanoacrylic acid (D9), and 3-(5-bis(4,4'-dimethoxydiphenylamino)styryl)thiophen-2-yl)-2-cyanoacrylic acid (D11) anchored onto TiO2 and were tested in dye-sensitized solar cell with a volatile electrolyte. The monochromatic incident photon-to-current conversion efficiency of these sensitizers is above 80%, and D11-sensitized solar cells yield a short-circuit photocurrent density of 13.

Tuning the HOMO and LUMO energy levels of organic chromophores for dye sensitized solar cells.

A series of organic chromophores have been synthesized in order to approach optimal energy level composition in the TiO2-dye-iodide/triiodide system in the dye-sensitized solar cells. HOMO and LUMO energy level tuning is achieved by varying the conjugation between the triphenylamine donor and the cyanoacetic acid acceptor. This is supported by spectral and electrochemical experiments and TDDFT calculations.

An iron carbonyl approach to the influenza neuraminidase inhibitor oseltamivir.

A novel synthetic route towards oseltamivir, an influenza neuraminidase inhibitor, has been achieved employing a cationic iron carbonyl complex, providing an alternate pathway with the potential to access diverse analogues.

A novel organic chromophore for dye-sensitized nanostructured solar cells.

A novel and efficient polyene-diphenylaniline dye for dye-sensitized solar cells has been synthesized. The dye has a short synthesis route and is readily adsorbed on TiO2 under a variety of dye-bath conditions. The overall solar-to-energy conversion efficiency is over 5% in the preliminary tests, in comparison with the conventional N719 dye which gives 6% under the same conditions.