[en] Different compositions of Fe-doped tungsten trioxide thin films were synthesized on fluorine-doped tin oxide (FTO) glass substrate by sol-gel method, with ferrocene and tungstic acid as starting materials. The synthesized thin films was characterized with X-ray diffraction (XRD), scanning electron microscope (SEM), UV/Vis spectrophotometer and photoelectrochemical (PEC) analysis. The results show that the surface morphology of the thin films became rough and the grain size increased along with the concentration of Fe. Monoclinic structure of tungsten trioxide was obtained for all doped and undoped WO₃ and red-shift can be observed from UV-vis spectrum. Band gap reduced from 2.74 eV of undoped WO₃ thin films to 2.60 eV of 20 % Fe-doped WO₃ thin films. Photoactivities of all Fe-doped WO₃ are higher than undoped thin films. The highest photoactivities contributed by 5 % Fe-doped WO₃ films with photocurrent densities measured was 0.148 mA/ cm², which is 3 times higher compared to undoped WO₃. (author)

[en] Photoelectrochemical sensors were developed for the rapid detection of oxidative DNA damage induced by titanium dioxide and polystyrene nanoparticles. Each sensor is a multilayer film prepared on a tin oxide nanoparticle electrode using layer- by-layer self assembly and is composed of separate layer of a photoelectrochemical indicator, DNA. The organic compound and heavy metals represent genotoxic chemicals leading two major damaging mechanisms, DNA adduct formation and DNA oxidation. The DNA damage is detected by monitoring the change of photocurrent of the indicator. In one sensor configuration, a DNA intercalator, Ru(bpy)2 (dppz)2+ [bpy=2, 2' -bipyridine, dppz=dipyrido (3, 2-a: 2' 3'-c) phenazine], was employed as the photoelectrochemical indicator. The damaged DNA on the sensor bound lesser Ru(bpy)2 (dppz)2+ than the intact DNA, resulting in a drop in photocurrent. In another configuration, ruthenium tris(bipyridine) was used as the indicator and was immobilized on the electrode underneath the DNA layer. After oxidative damage, the DNA bases became more accessible to photoelectrochemical oxidation than the intact DNA, producing a rise in photocurrent. Both sensors displayed substantial photocurrent change after incubation in titanium dioxide / polystyrene solution in a time . dependent manner. According to the data, damage of the DNA film was completed in 1h in titanium dioxide / polystyrene solution. In addition, the titanium dioxide induced much more sever damage than polystyrene. The results were verified independently by gel electrophoresis and UV-Vis absorbance experiments. The photoelectrochemical reaction can be employed as a new and inexpensive screening tool for the rapid assessment of the genotoxicity of existing and new chemicals. (author)

[en] The Gratzel photoelectrochemical cell is a relatively new device that has the advantage of being significantly cheaper to produce than a bulk silicon solar cell. This paper examines sputtered titanium dioxide Gratzel devices specifically to discuss the practical implementation of such a device. In addition to the sputtered titanium dioxide coating, an electrical model is presented to aid in the design of components for a complete photovoltaic power system. The Gratzel cell exhibits a significant capacitance that can cause misleading measurements when tested on conventional equipment. The capacitance and the reverse bias conditions are presented as an electrical model for use in circuit simulators such as SPICE or MCROCAP. Copyright (2001) The Australian Ceramic Society

[en] Photocurrent and H₂ production were demonstrated in an all solid-state photoelectrochemical cell employing gaseous methanol and water vapour at the photoanode. Open circuit photovoltage of around −0.4 V and short circuit photocurrent of up to 250 μA/cm² were obtained. At positive bias, photocurrent generation was limited by the irradiance, i.e., the amount of photogenerated charge carriers at the anode. Time constants and impedance spectra showed an electrochemical capacitance of the cell of about 15 μF/cm² in the dark, which increased with increasing irradiance. With only water vapour at the anode, the short circuit photocurrent was about 6% of the value with gaseous methanol and water vapour. The photoanode and electrocatalyst on carbon paper support were affixed to the proton conducting membrane using Nafion^® as adhesive, an approach that yielded photocurrents up to 15 times better than that of a cell assembled by hot-pressing, in spite of the overall cell resistance of the latter being up to five times less than that of the former. This is attributed, at least partially, to reactants being more readily available at the photoanode of the better performing cell

[en] The claim is often made that efficiency is a key factor in determining the marketability of photovoltaic products. If this is the case, a strong correlation between the price of modules and their efficiency might be expected. This relationship is investigated using module pricing data that have recently become available. Conclusions are that there is little correlation between module price and efficiency in this data set and that some thin-film modules currently appear to attract a pricing premium. (Author)

[en] Underwater spherical photoelectrochemical cells aligned in three-dimensional electrolyte space convert injected sunlight into driving force for water splitting, which is analysed by a model calculation and verified in experiments. Sunlight is well absorbed via a number of bounces on Si, and trajectories of its rays are in a fractal-like scale-free system. Similar systems are applicable to general photoelectrochemical cells. (fast track communication)

[en] Various modifications of the titanium dioxide thin films have been done in fulfilling the photoelectrode requirements for photoelectrochemical water splitting reaction. In this study, surface passivation of TiO₂ by hematite-Fe₂O₃ was reported. Electrodeposition technique was used to deposit the Fe₂O₃ onto the TiO₂/ FTO film with variation of time. X-ray diffraction (XRD), Scanning Electron Microscope (SEM) and UV-Vis spectroscopic analyses were used to characterize the electrode. Plane-wave-based pseudopotential density functional theory (DFT) calculations were used to analyze the electronic structure and charge potential at the surface of the electrode. The photocurrent measurement showed that current density of TiO₂/ Fe₂O₃ electrode was higher than the TiO₂/ FTO under the same illumination intensity of 100 mWcm^-2. The highest current density was produced by 5 minutes electrodeposition of Fe₂O₃, which also shifted the absorption to visible region at the threshold wavelength of 518 nm. (author)

[en] The invention refers to the field of solar-to electric energy conservation and may be used for the creation of photoelectrochemical regenerating converters. Summary of the invention consists in that the photoelectrochemical solar battery includes a semiconducting photo-electrodes and a counter-electrode , placed into the electrolyte solution. The photo-electrode is made of the compounds A3B5, and in the capacity of electrolyte solution is used an aqueoua solution Na2SiO3. The result of the invention consists in the absorbtion from the electrtolyte solution of the ions SiO3 and HSiO3 on the photo-electrode working surface, that leads to a decrease in the corrosion of the latter

[en] It is well known that the optical and electronic structures of two-dimensional (2D) materials often show very strong layer-dependent properties. The properties can also be tuned by stacking configuration, which allows us to build electro and optical devices with the same material and the same thickness. Detailed understanding of the inter-layer interaction will help greatly in tailoring the properties of 2D materials for applications, e.g. in pn junction, transistors, solar cells and LEDs. Raman/Photoluminescence (PL) spectroscopy and imaging have been extensively used in the study of nano-materials and nano-devices. They provide critical information for the characterization of the materials such as electronic structure, optical property, phonon structure, defects, doping and stacking sequence. In this talk, we use Raman and PL techniques and electric measurements, as well as simulation to study 2- and 3-layer 2D samples. The Raman and PL spectra also show clear correlation with layer-thickness and stacking sequence. Electrical experiments and ab-initio calculations reveal that difference in the electronic structures mainly arises from competition between spin-orbit coupling and interlayer coupling in different structural configurations

[en] Photoelectrochemical(PEC) cell is a devise to convert photon energy to electrical or chemical energy using a semiconductor material as a photo-anode. Titania has been widely used for this application as a semiconductor material, even though it has a wide band-gap which is inappropriate for conversion of photo energy to electrical energy due to the poor absorption of visible light. Recently, dye sensitization became a good solution to increase the absorption of visible light. However, this approach includes several processes in fabrication which can be time consuming and inappropriate for commercialization. In this study, electron beam was irradiated to a silica and titania based hybrid polymer to form a semiconductor material which has a good visible light absorption property. This approach may be a very simple method to fabricate a photo-anode