Nuevo colorante orgánico para aplicación en celdas solares de sensibilización espectral

En este trabajo se caracterizó un nuevo material orgánico: 2,2´-dicianoacético-7,7´-bisdifenilamino-9,9´-spirobisfuoreno (SSD1), el cual tiene por finalidad reemplazar los complejos derivados de Rutenio, utilizados en celdas solares sensibilizadas espectralmente. Esta estructura posee un grupo spirobisfluoreno como centro estructural, el cual es sustituido con grupos donores (D) (Trifenilamina) y grupos aceptores (A) de electrones (ciano y carboxilo). Se evaluó la eficiencia de conversión de energía de los dispositivos construidos con depósitos de nanopartículas de TiO2 sensibilizadas con SSD1 y utilizando la cupla Γ/Γ3 como mediador redox. Las celdas exhibieron una corriente de cortocircuito (Jcc) de 8.9 mA/cm2, un voltaje de circuito abierto (Voc) de 0.61 V, y un Factor de llenado (FF) de 0.67, lo cual determina una eficiencia (η) de 3.75%.A new dye, SSD1, featuring two donor/acceptor chromophores aligned in a spiro configuration with two anchoring group separated at a distance of 10.05 Å (closely matching the distance between the adsorption sites of the anatase TiO2 surface), that undergoes efficient dye adherence on TiO2 films. A dye-sensitized solar cell incorporating SSD1 exhibited a short-circuit current of 8.9 mA cm–2, an open-circuit voltage of 0.63 V, a fill factor of 0.67, and a power conversion efficiency of 3.75%.Asociación Argentina de Energías Renovables y Medio Ambiente (ASADES

Nuevo colorante orgánico para aplicación en celdas solares de sensibilización espectral

En este trabajo se caracterizó un nuevo material orgánico: 2,2´-dicianoacético-7,7´-bisdifenilamino-9,9´-spirobisfuoreno (SSD1), el cual tiene por finalidad reemplazar los complejos derivados de Rutenio, utilizados en celdas solares sensibilizadas espectralmente. Esta estructura posee un grupo spirobisfluoreno como centro estructural, el cual es sustituido con grupos donores (D) (Trifenilamina) y grupos aceptores (A) de electrones (ciano y carboxilo). Se evaluó la eficiencia de conversión de energía de los dispositivos construidos con depósitos de nanopartículas de TiO2 sensibilizadas con SSD1 y utilizando la cupla Γ/Γ3 como mediador redox. Las celdas exhibieron una corriente de cortocircuito (Jcc) de 8.9 mA/cm2, un voltaje de circuito abierto (Voc) de 0.61 V, y un Factor de llenado (FF) de 0.67, lo cual determina una eficiencia (η) de 3.75%.A new dye, SSD1, featuring two donor/acceptor chromophores aligned in a spiro configuration with two anchoring group separated at a distance of 10.05 Å (closely matching the distance between the adsorption sites of the anatase TiO2 surface), that undergoes efficient dye adherence on TiO2 films. A dye-sensitized solar cell incorporating SSD1 exhibited a short-circuit current of 8.9 mA cm–2, an open-circuit voltage of 0.63 V, a fill factor of 0.67, and a power conversion efficiency of 3.75%.Asociación Argentina de Energías Renovables y Medio Ambiente (ASADES

Nuevo colorante orgánico para aplicación en celdas solares de sensibilización espectral

En este trabajo se caracterizó un nuevo material orgánico: 2,2´-dicianoacético-7,7´-bisdifenilamino-9,9´-spirobisfuoreno (SSD1), el cual tiene por finalidad reemplazar los complejos derivados de Rutenio, utilizados en celdas solares sensibilizadas espectralmente. Esta estructura posee un grupo spirobisfluoreno como centro estructural, el cual es sustituido con grupos donores (D) (Trifenilamina) y grupos aceptores (A) de electrones (ciano y carboxilo). Se evaluó la eficiencia de conversión de energía de los dispositivos construidos con depósitos de nanopartículas de TiO2 sensibilizadas con SSD1 y utilizando la cupla Γ/Γ3 como mediador redox. Las celdas exhibieron una corriente de cortocircuito (Jcc) de 8.9 mA/cm2, un voltaje de circuito abierto (Voc) de 0.61 V, y un Factor de llenado (FF) de 0.67, lo cual determina una eficiencia (η) de 3.75%.A new dye, SSD1, featuring two donor/acceptor chromophores aligned in a spiro configuration with two anchoring group separated at a distance of 10.05 Å (closely matching the distance between the adsorption sites of the anatase TiO2 surface), that undergoes efficient dye adherence on TiO2 films. A dye-sensitized solar cell incorporating SSD1 exhibited a short-circuit current of 8.9 mA cm–2, an open-circuit voltage of 0.63 V, a fill factor of 0.67, and a power conversion efficiency of 3.75%.Asociación Argentina de Energías Renovables y Medio Ambiente (ASADES

Photoinduced Charge Separation in Organic Organic Heterojunctions Based on Porphyrin Electropolymers. Spectral and Time Dependent Surface Photovoltage Study

Photoactive heterojunctions formed by porphyrin polymers were electrochemically generated and analyzed by both transient and spectral dependent surface photovoltage. Indium tin oxide/organic polymer heterojunction photovoltages showed to be dependent on the presence of Zn (II) as central metal on the porphyrin polymer structure. The porphyrin electropolymers were also successfully formed on the top of a poly 3,4-ethylenedioxythiophene layer, generated by electropolymerization. The presence of the hole transport polymer dramatically altered the formation and diffusion process of the photocarriers created by excitation of the porphyrin films. A marked increase in the generated photovoltages was observed when the porphyrin electropolymer external surfaces were modified with a layer of a strong electron acceptor (C60 buckminsterfullerene), showing that these heterojunctions could be used in the development of new solar energy technologies.Fil: Durantini, Javier Esteban. Universidad Nacional de Río Cuarto. Facultad de Ciencias Exactas Fisicoquímicas y Naturales. Departamento de Química; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Suárez Ramanzin, Maria Belen. Universidad Nacional de Río Cuarto. Facultad de Ciencias Exactas Fisicoquímicas y Naturales. Departamento de Química; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Santo, Marisa. Universidad Nacional de Río Cuarto. Facultad de Ciencias Exactas Fisicoquímicas y Naturales. Departamento de Química; ArgentinaFil: Durantini, Edgardo Néstor. Universidad Nacional de Río Cuarto. Facultad de Ciencias Exactas Fisicoquímicas y Naturales. Departamento de Química; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Dittrich, Thomas. Helmholtz Center Berlin for Materials and Energy; AlemaniaFil: Otero, Luis Alberto. Universidad Nacional de Río Cuarto. Facultad de Ciencias Exactas Fisicoquímicas y Naturales. Departamento de Química; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Gervaldo, Miguel Andres. Universidad Nacional de Río Cuarto. Facultad de Ciencias Exactas Fisicoquímicas y Naturales. Departamento de Química; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentin

Electrochemical generation of porphyrin porphyrin and porphyrin C60 polymeric photoactive organic heterojunctions

tPhotoactive organic organic interfaces are formed by electrochemical synthesis. The generation of por phyrin porphyrin and porphyrin C60heterojunctions over indium tin oxide electrodes by successiveelectropolymerization steps is described. Functionalized C60buckminsterfullerene holding a carbazolresidue and porphyrins containing carbazol and phenylamino moieties are able to form electrodepositedlayers by cyclic voltammetry. Photoinduced electron transfer between Zn II , free base porphyrins and C60films were analyzed by both, light modulated surface photovoltage spectroscopy and laser induced tran sient photovoltage. The results showed that the electrochemical generated polymeric heterojunctionsare able to produce photoinduced charge separated states, which could present a potential applicationin the design and construction of organic optoelectronic device

Synthesis and characterization of porphyrin electrochromic and photovoltaic electropolymers

New asymmetric porphyrins, with electroactive functionalities were synthesized. 5,15 Bis[4 N,N diphenylamino phenyl] 10,20 bis[3 N ethylcarbazoyl ]porphyrin and its Zn II derivative allow the electrochemical formation of conjugated, conducting and stable polymeric films over semitransparent indium tin oxide surface. The spectral changes observed upon oxidation of the films produced different colorations. The polymeric materials showed the generation of photoinduced charge separation states and charge migration upon porphyrin excitation, making them promising candidates for application in optoelectronics device

Photocurrent enhancement in dye-sensitized photovoltaic devices with titania–graphene composite electrodes

Photovoltaic performance of dye-sensitized solar cell (DSC) devices based on a new titania–graphene paste has been investigated using Impedance Spectroscopy (IS) technique. The results provide key information about device performance, clarifying that photocurrent increment is not related to lower charge transfer resistance, neither with a downshift of the Fermi level of the graphene titania semiconductor. The DSC devices constructed using titania–graphene paste and graphene thin films reach higher photocurrent and therefore higher efficiency than devices made with a commercial paste due to extra photocurrent generation, because the titania–graphene paste presents higher light harvesting in the visible region of the solar spectra combined with large scatter effect than the commercial titania paste

All-photonic molecular half-adder

One molecule acts as both an AND and an XOR Boolean logic gate that share the same two photonic inputs. The molecule comprises a half-adder, adding two binary digits with only light as inputs and outputs, and consists of three covalently linked photochromic moieties, a spiropyran and two quinolinederived dihydroindolizines. The AND function is based on the absorption properties of the molecule, whereas the XOR function is based on an off-on-off response of the fluorescence to the inputs that results from interchromophore excited-state quenching interactions. The half-adder is simple to operate and can be cycled many times