Characterization of cadmium-doped nZVI residuals: Structure, morphology, and photoelectrochemical properties

High conversion efficiency photoelectrochemical solar cells

Fabrication of single-step novel synthesis of ZnCd(S0.5Se0.5)2 thin films for photoelectrochemical (PEC) cell application

Enhancement of photoelectrochemical activity of nanocrystalline CdS photoanode by surface modification with TiO2 for hydrogen production and electricity generation

This study investigates the relationships among redox couple activity, electrolyte concentration, and efficiency in CdSe thin-film photoelectrochemical solar cells. A CdSe photo-electrode was prepared using the electro-depositing technique to produce well-staged layering of CdSe, followed by chemical bath deposition to produce a layer with an acceptable thickness to absorb enough photons to create a suitable amount of photocurrent. The CdSe photo-electrochemical cell was tested under various concentrations of a NaOH/Na2S/S electrolyte solution. The results showed that the activity of the redox couple greatly affected the efficiencies of the solar cells. Correlation plots between ionic strength and PEC efficiency with the Debye–Hückel equation yielded an R² value of 0.96, while those between ionic strength and photocurrent density had an R² value of 0.92. The correlation between concentration and PEC efficiency was much weaker. This paper highlights how optimal ionic activity increases the performance of photoelectrochemical solar cells, which consequently improves the conversion efficiency of solar energy.

2 - Materials for photoelectrochemical devices

A new type of photoelectrochemical (PEC) solar cell based on semiconductor septum (SC-SEP) photoelectrode has been shown to yield higher electrical power output than the conventional PEC solar cell. In the present study, photoelectrochemical, structural and compositional characteristics of the semiconductor component in n-CdSe/Ti septum, based SC-SEP, PEC solar cell, employing some reversible electrolyte systems under prolonged PEC operation (100 h), revealed that the CdSe photoelectrode undergoes deterioration through ‘Cd’ loss. For example, in the case of the cell Pt, 1 M 3S//n-CdSe/Ti//0.1 M AgNO3 (1 M = 1 mol dm−3), Pt; CdSe showed loss of ‘Cd’. This resulted in decrease of the cell power output (from Vph and Isc of 1.42 V and 20 mA cm−2 to 1.3 V and 13 mA cm−2 respectively). It has been shown in the present investigation that the best way to arrest semiconductor deterioration was by adding 0.1 M Se to polysulfide electrolyte thereby stabilizing this efficient SC-SEP, PEC cell.

Nanocrystalline FeS thin film used as an anode in photo-electrochemical solar cell and as hydrogen peroxide sensor

Optimization of semiconductor ns-TiO2-CuO admixed photoelectrode for photoelectrochemical solar cell in regard to hydrogen production

The world’s energy demand is continuously increasing. Non-renewable energy sources, such as petroleum and coal, are extremely limited. On the other hand, conversion efficiency of renewable energy sources into useful forms is insufficient. In our study, we pursued methods to make more efficient solar cells – in particular, photo-electrochemical (PEC) solar cells. We selected the Molybdenum diselenide (MoSe2) based PEC solar cell because of its high resistance to corrosion. First, we explored the relationship between light intensity and efficiency of PEC solar cells. We expected that corrosion of the PEC solar cell would increase with increase in intensity of incident light. Thus, we hypothesized that the efficiency of the solar cell would decrease with increased intensity of incident light. Further, we investigated the relationship between solar cell efficiency and electrolyte volume. We hypothesized that efficiency of PEC solar cell would increase as the electrolyte volume increased. We analyzed several parameters— such as light intensity, fill factor, efficiency, etc.—to draw conclusions. First, we found that percentage efficiency of PEC solar cell was proportional to (light intensity)-0.9. Further analysis showed that PEC solar cell performance was positively influenced by increasing the electrolyte volume. Data revealed that this increase in solar cell performance was more consequential at low intensities of light (around 10 mW/cm2). Our study could contribute to improving the quality of PEC solar cells and might help in the development of carbon-free hydrogen economy.

The presence of heavy metals in the industrial effluents has recently been a challenging issue for human health. Efficient removal of heavy metal ions from environment is one of the most important issues from biological and environmental point of view, and many studies have been devoted to investigate the environmental behavior of nanoscale zerovalent iron (NZVI) for the removal of toxic heavy metal ions, present both in the surface and underground wastewater. The aim of this review is to show the excellent removal capacity and environmental remediation of NZVI-based materials for various heavy metal ions. A new look on NZVI-based materials (e.g., modified or matrix-supported NZVI materials) and possible interaction mechanism (e.g., adsorption, reduction and oxidation) and the latest environmental application. The effects of various environmental conditions (e.g., pH, temperature, coexisting oxy-anions and cations) and potential problems for the removal of heavy metal ions on NZVI-based materials with the DFT theoretical calculations and EXAFS technology are discussed. Research shows that NZVI-based materials have satisfactory removal capacities for heavy metal ions and play an important role in the environmental pollution cleanup. Possible improvement of NZVI-based materials and potential areas for future applications in environment remediation are also proposed.

Photoelectrochemical and photovoltaic cell performances of thermally evaporated Cu3BiS3 thin films

Solar-to-electricity energy conversion and large scale electricity storage technologies are key to achieve a sustainable development of society. For energy conversion, photoelectrochemical solar cells were proposed as an economic alternative to the conventional Si-based technology. For energy storage, metal-ion batteries are a very promising technology. Titania (TiO2) based anodes are widely used in photoelectrochemical cells and have recently emerged as safe, high-rate anodes for metal-ion batteries. In both applications, titania interacts with electrolyte species: molecules and metal ions. Details of this interaction determine the performance of the electrode in both technologies, but no unified theoretical description exists, e.g., there is no systematic description of the effects of Li, Na insertion into TiO2 on solar cell performance (while it is widely studied in battery research) and no description of effects of surface adsorbents on the performance of battery anodes (while they are widely studied in solar cell research). In fact, there is no systematic description of interactions of electrolyte species with TiO2 of different phases and morphologies. We propose a computation-focused study that will bridge the two fields that have heretofore largely been developing in parallel and will identify improved anode materials for both photoelectrochemical solar cells and metal-ion batteries.

The solar cells have been used as most promising device to convert light energy into electrical energy. In this paper authors have attempted to fabricate Photoelectrochemical solar cell with semiconductor electrode using TMDCs. The Photoelectrochemical solar cells are the solar cells which convert the solar energy into electrical energy. The photoelectrochemical cells are clean and inexhaustible sources of energy. The photoelectrochemical solar cells are fabricated using WSe2crystal and electrolyte solution of 0.025M I2, 0.5M NaI, 0.5M Na2SO4. Here the WSe2crystals were grown by direct vapour transport technique. In our investigations the solar cell parameters like short circuit current (Isc) and Open circuit voltage (Voc) were measured and from that Fill factor (F.F.) and photoconversion efficiency (η) are investigated. The results obtained shows that the value of efficiency and fill factor of solar cell varies with the illumination intensities.

Photo-electrochemical hydrogen generation from water using solar energy. Materials-related aspects

Highly compact vertical array ZnO nanorods on the FTO coated glass was fabricated for photoelectrochemical cell of FTO/ZnO/electrolyte/platinum. ZnO nanorods were grown on the FTO substrate at room temperature via ammonia assisted rapid hydrolysis process technique. In typical process, ZnO nanorods were characterized by FESEM with vertical array oriented with average diameter and length of 48 nm and 218 nm, respectively. The sample was grown throughout the surface by using four cycle growth process. The photoelectrochemical cell property was studied in dark and under illumination of 100 mWcm-2 light. The cell exhibits photovoltaic effect with JSC of 0.22mAcm-2, VOC of 0.44 V, and conversion efficiency of 0.03%. Keywords: Vertical array ZnO nanorods, Photoelectrochemical solar cell