A new dye, SSD1, featuring two donor/acceptor chromophores aligned in a spiro configuration with anchoring groups separated at distance of 10.05 (closely matching the between adsorption sites anatase TiO(2) surface) undergoes efficient dye adherence on films. dye-sensitized solar cell incorporating SSD1 exhibited short-circuit current 8.9 mA cm(-2), an open-circuit voltage 0.63 V, fill factor 0.67, and power conversion efficiency 3.75%.

We have synthesized a novel 9,9'-spirobifluorene-cored donor−acceptor (D−A) bichromophore system in which the electron-donating (D) moieties are triphenylamine (TPA) and carbazole (CBZ) groups electron-withdrawing (A) 1,3,4-oxadiazole (OXD) groups. The electron-deficient OXD efficiently blocked radical cations delocalization between two terminal TPA groups, rendering electropolymerization of feasible. resulting polymer could be cross-linked further at higher oxidation potentials through...

Carotenoids (Car) act as "wires" that discharge unwanted electrons in the reaction center of higher plants. One step this "side-path" electron conduction is thought to be mediated by Car oxidation. We have carried out direct measurements conductance single-Car molecules under potential control a membrane-mimicking environment, and we found when are oxidized enhanced electronic decay constant (beta) decreased. However, neutral molecule may already conductive enough account for observed transfer rates.

The synthesis and photophysical, electrochemical, spectroelectrochemical characterization of a novel donor−acceptor (D−A) bichromophore system composed two D−A segments linking through spiro center are reported. electron-donating (D) moieties triphenylamine (TPA) groups, whereas the electron-withdrawing (A) cyano groups. particular "spiro" configuration that perpendicularly bonds chromophores by tetrahedral carbon, impedes orbital interactions between branches. Thus, TPA substituents act...

Lead sulfide (PbS) nanoparticles were synthesized by chemical methods with different sizes and capping ligands (oleic acid, myristic hexanoic acid), avoiding ligand exchange procedures, to study the effect of characteristics on their energy levels band gap values. Experimental results (UV-vis-NIR, Fourier transform infrared, Raman spectroscopies, cyclic voltammetry, transmission electron microscopy, loss spectroscopy) showed a marked influence nature electro-optical properties PbS very...

We describe the morphological, electrochemical, spectroelectrochemical characterization, and electrochromic device properties of films poly(2,2'-[10-methyl-3,7-phenothiazylene]-6,6'-bis[4-phenylquinoline]) (PPTZPQ). Cyclic voltammograms PPTZPQ polymer showed reversible electrochemical oxidation accompanied with a color change that was switchable as function potential. However, reduction behavior unstable caused loss effect. The interpreted combination constituent donor acceptor moieties. Two...

Near-IR dye sensitized solar cells are very interesting due to their potential applications in panchromatic cells, semi-transparent windows and tandem cells. In this work we show the utilization of axially anchored Si-naphthalocyanine spectral sensitization TiO2 nanostructured photoelectrodes. We report first successful evaluation a naphthalocyanine production photocurrent with maximum incident photon current efficiency (IPCE) at λ ∼ 790 nm.

Electroactive end-capped dendritic macromolecules were designed and synthesized. Their structures contain triphenylamine moieties as part of the core or dendrons. The electrogenerated films produced with these monomers behaved conductive polymers that can be reversible charged, both in peripheral units. design dendrimer introduction systematic changes allows to establish relationships between their electro-optical properties molecular structural parameters. polymeric material hold good...

A convenient procedure for the synthesis of porphyrin derivative dyads is described. The consist a free base covalently linked to zinc or ferrocene by an amide bond. 5-(4-Substituted phenyl)-10,15,20-tris(4-methylphenyl) porphyrins were synthesized from meso-(4-methylphenyl) dipyrromethanes 1, which was obtained with appreciable yield (83%). reaction dipyrromethane 1 mixture two appropriate substituted benzaldehydes affords desired meso-substituted porphyrins, can be easily separated flash...

The electrochemistry and radical ion annihilation electrogenerated chemiluminescence (ECL) of 9,9'-spirobifluorene-bridged bipolar systems containing 1,3,4-oxadiazole-conjugated oligoaryl triarylamine substituents were investigated. stability the oxidized spirobifluorenes was improved by functionalization with centers. These donor−acceptor (DA) compounds exhibited a good fluorescence efficiency an emission maximum that correlated potential difference between anion cation formation,...

Free-base (P), Zn(II) (P(Zn)), Cu(II) (P(Cu)), Pd(II) (P(Pd)), Ni(II) (P(Ni)), and Co(II) (P(Co)) 5-(4-carboxyphenyl)-10,15,20-tris(4-methylphenyl) porphyrins were designed synthesized to be employed as spectral senzitizers in photoelectrochemical cells. The dyes studied adsorbed on SnO(2) nanocrystalline semiconductor also Langmuir-Blodgett film ITO electrodes order disclose the effect of molecular packing properties. Electron injection yields obtained by fluorescence quenching analysis...

This Article describes the synthesis and physical properties of two bipolar starburst monomers: 1,3,5-tris{5-(7-(carbazol-9-yl)-(9,9′-spirobifluoren-2-yl)-1,3,4-oxadiazol-2-yl}benzene (OXD-CBZ) 1,3,5-tris[7-diphenyl-(9,9′-spirobifluorene)-1,3,4-oxadiazoyl]benzene (OXD-DPA) featuring an electron-deficient tris(1,3,4-oxadiazole)phenylene ring as interior core bridged by rigid spirobifluorene units to terminal electroactive carbazole (CBZ) diphenylamino (DPA) groups. The electronic absorption...

A new donor/acceptor (D-A) spiro dye (SCPDT1) featuring two bithiophene units, connected through an sp(3)-hybridized carbon atom, was prepared by a multistep synthetic sequence involving the convenient assembly of system under mild catalytic conditions. The photocurrent spectrum dye-sensitized solar cells incorporating SCPDT1 covers spectral region ranging from 350 to 700 nm and reaches wide maximum ~80% in 420-560 range. Power conversion efficiencies up 6.02% were obtained.

Spectroscopic and photodynamic properties of polymeric films bearing porphyrin units have been studied in both solution containing photooxidizable substrates vitro on Escherichia coli Candida albicans microorganisms. The were formed by electrochemical polymerization 5,10,15,20-tetra(4-N,N-diphenylaminophenyl)porphyrin (H2P-film) its complex with Pd(II) (PdP-film) optically transparent indium tin oxide (ITO) electrodes. Absorption spectroscopic studies show the characteristic Soret Q bands...

A series of structurally related sensitizers containing fluorene as a π-conjugated central core have been synthesized, characterized, and applied in the development dye-sensitized solar cells (DSSCs). The new electron donor (diphenylamine)–acceptor (cyanoacrylic acid) D-π-A molecular structures hold perfluoro-tert-butyl substituents different positions. It is demonstrated that fluorous substitution pattern remarkably affects behavior dyes photosensitizers DSSCs, leading to an improvement...

With a power conversion efficiency (PCE) exceeding 22 %, perovskite solar cells (PSCs) have thrilled photovoltaic research. However, the interface behavior is still not understood and hot topic of research: different processes occur over hierarchy timescales, from femtoseconds to seconds, which makes physics intriguing. Herein, through femtosecond transient absorption spectroscopy with spectral coverage extending into crucial IR region, ultrafast interface-specific at standard newly...

Sensitized photocurrent generation is observed with a porphyrin dyad (PZn-P) and its structural moieties: 5-(4-carboxyphenyl)-10,15,20-tris(4-methylphenyl) (P) Zn(II) (PZn). The dyes were adsorbed to saturation on nanocrystalline SnO2 thin film, employed as working electrode in photoelectrochemical cell. metallized unmetallized moieties possess different singlet state energies redox properties. In both, solution state, nearly complete singlet−singlet energy transfer from the PZn P has been...

The generation of photoelectrical effects through the spectral sensitization wide band gap (SnO2) nanostructured semiconductor electrode by excitation a novel porphyrin−fullerene (P−C60) dyad is reported. P−C60 was synthesized from 5-(4-amidophenyl)-10,15,20-tris(4-methoxylphenyl) porphyrin (P) linked to 1,2-dihydro-1,2-methoxyphenyl [60]-61-carboxilic acid (acid-C60) an amide bond. Anodic photocurrents and photovoltages are observed under visible irradiation ITO/SnO2/ electrodes, although...

We report the synthesis and structural characterization of two dumbbell-shaped dendrimers incorporating 9-phenylcarbazole units as dendrons, well their thermal, morphological, photophysical, electrochemical properties.

Modulated charge separation has been investigated by surface photovoltage spectroscopy in the fixed capacitor arrangement for four different fluorene compounds adsorbed from highly diluted solutions at ultra-thin nanoporous TiO2 (np-TiO2), Au and ITO surfaces. Donor (–N(C6H5)2) acceptor moieties (–CN, –COOH) were linked or spirobisfluorene cores chain length changed introducing thiophene. electron injection intramolecular transport separated directed adsorption of spiro surfaces...

The electrochemistry of a series non-symmetric synthetic carotenoids, with different conjugated double bounds chain lengths (5 to 11) is reported. values the first oxidation potentials carotenoids were evaluated by digital simulation experimental cyclic voltammograms. There clear relationship between calculated (AM1) HOMO energies neutral their length, indicating that change solvation energy small throughout series, and electron-donating ability increases length chain. Carotenoids had been...

The electrochemical polymerization conditions for the synthesis of spirobifluorene-based polymer (EF-CN1) films with adequate properties to be applied in an organic light emitting diode (OLED) were studied. We demonstrate that, after optimization parameters polymerization, we able obtain a conducting polymeric film very smooth surface, absence pinholes, and high optoelectronic activity, which was compatible as efficient hole transporting layer OLED. deposited polymers, obtained through drop...