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In this study, graphene oxide sheet-polyaniline (GOS-PANI) nanocomposite was prepared through in-situ polymerization/deposition method for using as the counter electrode of dye-sensitized solar cell (DSSC). The fluorine-doped tin oxide (FTO) coated glass was immersed into the solution of the aniline and graphite oxide (GO) during the polymerization of PANI. The GOS-PANI nanocomposite was in-situ deposited onto the surface of the FTO glass. X-ray diffraction patterns indicate that the multi-layered graphene oxide sheets (GOS) were exfoliated by the chain segments of PANI. The images of scanning electron and atomic-force microscopes confirmed that the GOS were well distributed in the nanorod-type PANI based thin film. The presence of the synergistic effect of PANI and GO led to the higher electrochemical catalytic activity of GOS-PANI nanocomposite than that of GO or PANI. As a result, better PV performance was observed for DSSCs based on the GOS-PANI electrode as compared to that of the DSSC sample based on the PANI electrode. The highest photo-energy conversion efficiency (6.55 %) was obtained for the GOS-PANI electrode based DSSC sample. [ABSTRACT FROM AUTHOR]

ABSTRACT In this study, photovoltaic (PV) properties of dye-sensitized solar cells (DSSCs) incorporated with graphene oxide nanosheet-polyaniline (GOS-PANI) nanohybrid/poly(ethylene oxide) (PEO) blend gel electrolytes were investigated. Chemical structure and composition of GOS-PANI nanohybrids were characterized by Raman spectroscopy and X-ray photoelectron spectroscopy. The images of transmission electron microscopy revealed that PANI nanorods were anchored to the single-layered GOS for the GOS-PANI nanohybrids. Ionic conductivities of the GOS-PANI/PEO-based gel electrolytes were measured using a conductivity meter. The electrochemical catalytic activities of the GOS-PANI nanohybrids were determined through cyclic voltammetry. These GOS-PANI nanohybrids were served as the extended electron transfer materials and catalyst for the electrochemical reduction of I3−. Due to the enhancement of the ionic conductivity and electrochemical catalytic activity of the gel electrolyte, better PV performance was observed for the DSSCs based on the GOS-PANI containing electrolytes as compared to the pristine PEO electrolyte-based DSSC sample. Moreover, PV performances of the GOS-PANI/PEO-based DSSCs were closely related to the PANI content of GOS-PANI nanohybrids. The highest photo-energy conversion efficiency (5.63%) was obtained for an optimized GOS-PANI/PEO (5:95, w/w) blend gel electrolyte-based DSSC sample. © 2013 Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2014, 52, 321-332 [ABSTRACT FROM AUTHOR]

In this study, the photovoltaic properties of the dye sensitized solar cells (DSSCs) were enhanced by the incorporation of the polyethylene oxide (PEO) intercalated graphite oxides sheets (GO-P) or PEO surface grafted carbon nanotubes (CNT-P) into the PEO gel electrolytes. The PEO modified carbon materials were served as the extended electron transfer materials, and the catalysts for the electrochemical reduction of I. The ionic conductivity of PEO gel electrolyte was not significantly influenced by the incorporation of GO-P or CNT-P. Because of the high catalytic activities, the incorporation of GO-P or CNT-P into the gel electrolyte is favorable for decreasing the charge transfer and recombination resistances. Therefore, better PV performance was observed for the DSSCs based on the GO-P/PEO or CNT-P/PEO electrolytes as compared to the PEO electrolyte based DSSCs. The photoelectric conversion efficiencies of DSSCs were respectively enhanced by 19 % and 32 % via the incorporations of GO-P and CNT-P. [ABSTRACT FROM AUTHOR]

This study develops a series of titanium oxide electrode-based N719 dye-sensitized solar cells (DSSCs) using quaternized ammonium iodide containing main-chain and star-shaped polyfluorene (MPF-E and SPF-E) electrolyte solutions. The electrochemical impedance and photovoltaic properties of the polyfluorene electrolyte-based DSSCs were studied and compared to those of the poly(ethylene oxide) (PEO) electrolyte-based DSSCs. As with the PEO electrolyte-based DSSCs, the recombination impedance increased with increase in the polymer content for the MPF-E electrolyte-based DSSCs, whereas the photovoltaic performance did otherwise. Nevertheless, the reduction in the photovoltaic properties was not significant for the SPF-E electrolyte-based DSSCs. The electrochemical impedance and photovoltaic properties of the different polymer-based DSSCs are also discussed as a function of the polymer concentration. Copyright © 2010 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Abstract: Enhanced photovoltaic performances of N719 dye-sensitized solar-cells were achieved by modifying the titanium oxide (TiO2) electrode-sensitized dye interface. Surface of TiO2 thin film electrode was coated with a calcium oxide (CaO) or lithium fluoride (LiF) thin layer, respectively, in a thermal deposition chamber. As compared to a cell using a bare TiO2 nanoparticle (NTP) electrode, the solar energy conversion efficiency (η) was enhanced by 15.1% and 12.8% for the surface of a NTP electrode coated with CaO and LiF, respectively. Moreover, for the surface of a TiO2 nanotube electrode respectively coated with CaO and LiF, the efficiency was enhanced by 4.8% and 11.6%. This increase in efficiency is attributed to an increase in the adsorption of N719 dye on the CaO or LiF coated TiO2 thin film electrodes, and the formation of a potential barrier by a CaO or LiF interlayer at the TiO2 electrode-sensitized dye interface. [Copyright &y& Elsevier]

In this study, an Ag2S–CdS nanocomposite (AC11) was prepared through chemical co-precipitation of silver nitrate and cadmium acetate in an aqueous solution of thiourea. We then synthesized PACI, a nanocomposite of polyaniline (PANI) and AC11, through in situ polymerization of aniline in an AC11-containing solution, resulting in uniform embedding of the AC11 nanoparticles in the PANI fibers. Moreover, we synthesized the nanocomposite PACO through deposition of the AC11 nanoparticles on the surface of the PANI fibers. PANI, PACI, and PACO were then spin-coated onto conducting glasses to form PANI-S, PACI-S, and PACO-S counter electrodes, respectively, for dye-sensitized solar cells (DSSCs). Cyclic voltammetry revealed that the electrochemical catalytic activity of the PACI-S electrode was much higher than those of the PANI-S and PACO-S electrodes. Furthermore, the photovoltaic properties of the PACI-S-based DSSC were much better than those of the PANI-S- and PACO-S-based DSSCs. Indeed, the highest short-circuit current density (12.06 mA/cm2), open-circuit voltage (0.72 V), fill factor (0.58), and photoenergy conversion efficiency (5.04%) were those of the DSSC featuring PACI-S as the counter electrode. [ABSTRACT FROM AUTHOR]

A series of imidazolium-containing ionic liquid copolymers has been synthesized through free radical copolymerizations of an imidazolium-containing ionic liquid monomer (MEBIm-I), poly(ethylene glycol) methyl ether methacrylate (POEM), and acrylonitrile at various molar ratios. A thorough investigation has been conducted to study the effects of the chemical structure on the ionic conductivities, ionic diffusion coefficients, and catalytic activities of the ionic liquid copolymers. The presence of the ethylene oxide segments enhanced the ionic diffusion coefficients and conductivities of the POEM-containing ionic liquid copolymers. The incorporation of suitable contents of acrylonitrile units enhanced the catalytic activities of the ionic liquid copolymers. The photovoltaic and electrochemical impedance properties of dye-sensitized solar cells (DSSCs) assembled from these ionic liquid copolymer–based electrolytes have been evaluated. A maximum power conversion efficiency of 7.57%, with a maximum short-circuit current density of 16.0 mA cm−2, an open-circuit voltage of 0.84 mV, and a fill factor of 57.0%, has been achieved for DSSCs based on the ionic liquid copolymers (architecture: fluorine-doped tin oxide (FTO) glass/TiO 2 /N719 dye/ionic liquid polymer–based electrolyte/Pt/FTO glass) under AM 1.5 illumination with an intensity of 100 mW cm−2. Image 1 • Synthesis of novel imidazolium-containing ionic liquid copolymers (ILPs) for DSSCs. • Use of these ILPs as gel electrolytes in DSSCs. • Chemical structure of the ILPs affects the photovoltaic performance of these DSSCs. • High efficiency displayed by the ILP-based DSSCs. [ABSTRACT FROM AUTHOR]