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TiO2 Electrodes (tio2 + electrode)

Distribution by Scientific Domains
Chemistry71%
Polymers and Materials Science28%

Selected Abstracts

A High-Speed Passive-Matrix Electrochromic Display Using a Mesoporous TiO2 Electrode with Vertical Porosity

ANGEWANDTE CHEMIE, Issue 23 2010
Wu Weng
Klar und deutlich: Ein leistungsstarkes und schnelles elektrochromes Display (ECD) mit passiver Matrix wurde aus einem Leukofarbstoff und einer nanoporösen TiO2 -Elektrode konstruiert (siehe Bild). Die senkrechten Poren verhindern eine Bewegung der Farbstoffmoleküle und führen dadurch zu klaren Bildern bei hohen Frequenzen. Mit einer farbigen Variante dieses ECD könnten konkurrenzfähige elektrische Reflektivdisplays entwickelt werden. [source]

Improved-Performance Dye-Sensitized Solar Cells Using Nb-Doped TiO2 Electrodes: Efficient Electron Injection and Transfer

ADVANCED FUNCTIONAL MATERIALS, Issue 3 2010
Xujie Lü
Abstract Well-crystallized Nb-doped anatase TiO2 nanoparticles are prepared by a novel synthetic route and successfully used as the photoanode of dye-sensitized solar cells (DSSCs). The homogenous distribution of Nb in the TiO2 lattice is confirmed by scanning transmission electron microscopy (STEM) elemental mapping and line-scanning analyses. After Nb doping, the conductivity of the TiO2 powder increases, and its flat-band potential (Vfb) has a positive shift. The energy-conversion efficiency of a cell based on 5.0,mol% Nb-doped TiO2 is significantly better, by about 18.2%, compared to that of a cell based on undoped TiO2. The as-prepared Nb-doped TiO2 material is proven in detail to be a better photoanode material than pure TiO2, and this new synthetic approach using a water-soluble precursor provides a simple and versatile way to prepare excellent photoanode materials. [source]

Comparison of Trap-state Distribution and Carrier Transport in Nanotubular and Nanoparticulate TiO2 Electrodes for Dye-Sensitized Solar Cells

CHEMPHYSCHEM, Issue 10 2010
Raheleh Mohammadpour
Abstract Dye-sensitized solar cells (DSCs) with nanotubular TiO2 electrodes of varying thicknesses are compared to DSCs based on conventional nanoparticulate electrodes. Despite the higher degree of order in one-dimensional nanotubular electrodes, electron transport times and diffusion coefficients, determined under short-circuit conditions, are comparable to those of nanoparticulate electrodes. The quasi-Fermi level, however, is much lower in the nanotubes, suggesting a lower concentration of conduction band electrons. This provides evidence for a much higher diffusion coefficient for conduction band electrons in nanotubes than in nanoparticulate films. The electron lifetime and the diffusion length are significantly longer in nanotubular TiO2 electrodes than in nanoparticulate films. Nanotubular electrodes have a trap distribution that differs significantly from nanoparticulate electrodes; they possess relatively deeper traps and have a characteristic energy of the exponential distribution that is more than two times that of nanoparticulate electrodes. [source]

Towards Optimization of Materials for Dye-Sensitized Solar Cells

ADVANCED MATERIALS, Issue 45 2009
Yanhong Luo
Abstract Dye-sensitized solar cells (DSCs) have received widespread attention owing to their low cost, easy fabrication, and relatively high solar-to-electricity conversion efficiency. Based on the nanocrystalline TiO2 electrode, Ru-polypyridyl-complex dye, liquid electrolyte with I,/I3, redox couple, and Pt counter electrode, DSCs have already exhibited an efficiency above 11% and offer an appealing alternative to conventional solar cells. However, further improvements in the efficiency and stability are still required to drive forward practical application. These improvements require the cooperative optimization of the component materials, structures, and processing techniques. In this Research News article, recent progress in DSCs made by our group are reviewed, including some novel approaches to the synthesis of solid-state and environmentally friendly electrolytes, the fabrication of alternative low-cost nanostructural electrodes, and the control of recombination at the interfaces. [source]

Silanol dyes for solar cells: higher efficiency and significant durability

APPLIED ORGANOMETALLIC CHEMISTRY, Issue 3 2010
Masafumi Unno
Abstract Azobenzene-containing silanol dyes were synthesized, and their applicability to dye-sensitized solar cells was investigated. Silanol dyes showed better effectiveness when compared with conventional carboxy-substituted azobenzene dyes. Moreover, silanol dyes showed better durability than carboxyl dyes; ,90% of silanol dyes remained intact on the TiO2 electrode of the solar cell after being immersed in water for 96 h, whereas in the case of carboxy dyes this figure was less than 20%. Copyright © 2010 John Wiley & Sons, Ltd. [source]

Synthesis, Characterization, and Sensitizing Properties of Heteroleptic RuII Complexes Based on 2,6-Bis(1-pyrazolyl)pyr­idine and 2,2,-Bipyridine-4,4,-dicarboxylic Acid Ligands

EUROPEAN JOURNAL OF INORGANIC CHEMISTRY, Issue 36 2007
Athanassios I. Philippopoulos
Abstract Starting from the Ru(bpp)Cl3 precursor (1), a family of novel heteroleptic RuII complexes of the general formulae [Ru(bpp)(dcbpyH)(X)] [X = Cl, (2a), NCS,, (3)] and Na[Ru(bpp)(dcbpy)(CN)] (4) with the ligands 2,6-bis(1-pyrazolyl)pyridine (bpp) and 2,2,-bipyridine-4,4,-dicarboxylic acid (dcbpyH2) has been synthesized, spectroscopically characterized, and attached to nanocrystalline TiO2 electrodes to be tested as solar cell sensitizers. Addition of HCl to (2a) led to the corresponding cationic derivative [Ru(bpp)(dcbpyH2)Cl]Cl (2b). All complexes were characterized by FT-IR, FT-Raman, UV/Vis, 1H NMR spectroscopy, elemental analysis, and mass spectrometry. Complex 4 and the previously reported [Ru(bdmpp)(dcbpyH2)Cl](PF6) (5) [bdmpp is 2,6-bis(3,5-dimethyl-1-pyrazolyl)pyridine] were characterized by single-crystal X-ray diffraction. The photo-electochemical properties of the dyes 2,4 were investigated and the efficiency of the corresponding dye-sensitized solar cells was compared to the sensitizing performance of the cis -[Ru(dcbpyH)2(NCS)2](NBu4)2 (N719) dye.(© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2007) [source]

Comparison of Trap-state Distribution and Carrier Transport in Nanotubular and Nanoparticulate TiO2 Electrodes for Dye-Sensitized Solar Cells

CHEMPHYSCHEM, Issue 10 2010
Raheleh Mohammadpour
Abstract Dye-sensitized solar cells (DSCs) with nanotubular TiO2 electrodes of varying thicknesses are compared to DSCs based on conventional nanoparticulate electrodes. Despite the higher degree of order in one-dimensional nanotubular electrodes, electron transport times and diffusion coefficients, determined under short-circuit conditions, are comparable to those of nanoparticulate electrodes. The quasi-Fermi level, however, is much lower in the nanotubes, suggesting a lower concentration of conduction band electrons. This provides evidence for a much higher diffusion coefficient for conduction band electrons in nanotubes than in nanoparticulate films. The electron lifetime and the diffusion length are significantly longer in nanotubular TiO2 electrodes than in nanoparticulate films. Nanotubular electrodes have a trap distribution that differs significantly from nanoparticulate electrodes; they possess relatively deeper traps and have a characteristic energy of the exponential distribution that is more than two times that of nanoparticulate electrodes. [source]