Dye-sensitized solar cells fabricated using ordered arrays of titania nanotubes (tube lengths 5, 10, and 20 microm) grown on titanium have been characterized by a range experimental methods. The collection efficiency for photoinjected electrons in the is close to 100% under short circuit conditions, even microm thick nanotube array. Transport, trapping, back transfer studied detail complementary techniques. Analysis results has shown that electron diffusion length (which depends coefficient...

CdS/CdSe-sensitized nanostructured SnO(2) solar cells exhibiting record short-circuit photocurrent densities have been fabricated. Under simulated AM 1.5, 100 mW cm(-2) illumination, photocurrents of up to 17.40 mA are obtained, some 32% higher than that achieved by otherwise identical semiconductor-sensitized (SSCs) employing TiO(2). An overall power conversion efficiency 3.68% has for the SnO(2)-based SSCs, which compares very favorably efficiencies obtained TiO(2)-based SSCs. The...

Varying Li+ concentration in the electrolyte of dye-sensitized solar cells equipped with compact TiO2 blocking layers is found to alter mean slopes semilogarithmic open-circuit photovoltage−intensity and dark current−voltage plots. Almost identical values ideality factor or transfer coefficient are required fit data under illumination for each concentration. It that cell characteristics become progressively more "ideal" as increased, a ca.1 1 M electrolyte. We find trends well fitted using...

Semiconductor-sensitized TiO2 solar cells employing CdSe as a light absorber demonstrate superior photovoltaic performance to the best-performing cascaded CdS/CdSe with practically identical optical density in study. A careful comparison between and sensitized reveals that while CdS can greatly promote subsequent growth of cascade electrodes hence harvesting, presence buffer layer impedes injection electrons from accelerates charge recombination at TiO2/sensitizer interface. As result,...

Dye-sensitized solar cells with power conversion efficiencies of up to 6.5% have been fabricated using a cobalt tris-bipyridyl redox mediator the cis-diisothiocyanato-(2,2′-bipyridyl-4,4′-dicarboxylic acid)-(2,2′-bipyridyl-4,4′-dinonyl) ruthenium(II) (Z907) sensitizer. This represents significant improvement in efficiency compared previous reports ruthenium sensitizers. In situ near-IR transmittance measurements conjunction electrochemical impedance spectroscopy used explain difference...

Reliable quantification of parameters influencing the efficiency dye-sensitized solar cells (DSCs) is essential to guide device optimization and improve fundamental understanding operation. The small-perturbation electron diffusion length (Ln) in DSCs has been determined by electrochemical impedance spectroscopy analysis incident photon-to-collected-electron conversion (IPCE) spectra. When measurement conditions are chosen so that recombination can be treated as first-order free...

The performance of dye-sensitized solar cells (DSCs) depends on the competition between transport and interfacial recombination electrons. A key parameter in this context is electron diffusion length, which given by Ln = (Dτ)1/2, where D τ are, respectively, coefficient lifetime mobile new approach to reliable estimation described, involves use a titanium contact measure short-circuit value quasi-Fermi level side TiO2 film furthest from anode contact. This information used define conditions...

It is widely believed that the prototypical ruthenium dyes N719 and Z907 are regenerated by iodide with near unity quantum yield following photo-oxidation in dye-sensitized solar cells (DSCs). However, incident photon-to-current efficiency (IPCE) of DSCs using these decreases increasing forward bias, limiting power conversion (η) compared to hypothetical constant-IPCE case. This phenomenon could arise due incomplete regeneration, but despite important implications for cell efficiency, it has...

Mesoporous SnO2 spheres of tunable particle size were synthesized for the first time by facile electrochemical anodization tin foil in alkaline media. As process involves no sophisticated reactor or toxic chemicals, and proceeds continuously under ambient conditions, it provides an economic way synthesizing nanostructured on a large scale. Structural characterization indicates that these spherical particles consist agglomeration nanocrystals, resulting high internal surface area. This makes...

Regeneration of the sensitizing dye in dye-sensitized solar cells (DSCs) is frequently studied using transient absorption (TA) technique. However, TA measurements are generally not performed complete DSCs at maximum power point (MPP) on current–voltage (j–V) characteristic, and electron concentration nanocrystalline TiO2 films used these devices often well characterized, which may lead to results that relevant actual cell operation. Here, regeneration kinetics were MPP open circuit (where...

Ferrites and ferrite-based composites are known for their fascinating magnetic properties, varied redox chemistry, good stability, excellent catalytic all of which make them useful a growing range energy-related applications. The present review provides concise summary the basic properties ferrites, an overview applicable synthetic methods, recent advances related to application ferrites in photoelectrochemical cells, photocatalytic CO2 reduction, batteries, supercapacitors, microbial fuel...

The organic redox mediator tetramethylformaminium disulfide/tetramethylthiourea was evaluated in dye-sensitized nanocrystalline TiO2 solar cells, as an alternative to the conventional I3−/I− couple. Devices were optimized by judicious variation of electrolyte composition and selection sensitizing dye. best performance cells incorporating this achieved using a metal-free indoline-based sensitizer (D131). It found that ruthenium based sensitizers (e.g. Z907) exhibited inferior performance,...

Compact nickel oxide (NiO) thin films were prepared on various substrates via a simple spray pyrolysis technique. Morphological and structural characterization indicates that these NiO are very uniform in thickness (∼100 nm) possess the bunsenite crystal structure. Optical measurements show highly transparent with band gap of 3.70 ± 0.05 eV. Mott-Schottky plots obtained from electrochemical impedance spectroscopy reveal as-deposited fluorine-doped tin (FTO) glass behaves as p-type...

Replacing the nonyl groups on solar cell dye Ru(4,4′-carboxylic acid-2,2′-bipyridine)(4,4′-dinonyl-2,2′-bipyridine)(NCS)2 (Z-907) with amino results in a marked decrease performance. This is despite fact that derivative (Z-960) has more favourable light absorption characteristics than Z-907 when used thick nanocrystalline TiO2 layers. Electron transfer to electrolyte from exposed fluorine-doped tin oxide (FTO) substrate particularly fast cells employing Z-960 if compact blocking layer not...

The optical band gap of the light absorber and alignment its bands with underlying wide metal oxide are critical for efficient harvesting charge separation in semiconductor-sensitized solar cells (SSCs). In practice, these two requirements however not always fulfilled concomitantly SSCs. Favourable CdSe-sensitized TiO2 requires utilization quantum sized CdSe, which causes great losses long wavelength photons due to confinement effects. present study, ternary cadmium sulfoselenide...