International Journal of Photoenergy

https://www.hindawi.com/journals/ijp/

List of Papers (Total 2,712)

Performance Modelling of Dual Air/Water Collector in Solar Water and Space Heating Application

In the present work, the detailed mathematical model of a dual air/water solar collector (DAWC) has been developed and experimentally verified. To demonstrate the application of the DAWC, three buildings with different energy performance levels and three building locations were chosen in analyzed case studies. Four solar collector systems were compared with one another. The solar...

Donor-π-Conjugated Spacer-Acceptor Dye-Sensitized Solid-State Solar Cell Using CuI as the Hole Collector

Dye-sensitized solid-state solar cells (DSSCs) replacing the liquid electrolyte with a p-type semiconductor have been extensively examined to solve the practical problems associated with wet-type solar cells. Here, we report the fabrication of a solid-state solar cell using copper iodide (CuI) as the hole conductor and alkyl-functionalized carbazole dye (MK-2) as the sensitizer...

Design, Electrical, and Optical Modelling of Bulk Heterojunction Polymer Solar Cell

The energy scenario today is focused on the development and usage of solar cells, especially in the paradigm of clean energy. To readily create electron and hole pairs, solar cells utilize either photoactive or photosensitive components. A bulk heterojunction (BHJ) is a nanolayer consisting of donor and acceptor components with a large interpenetrated acceptor and donor contact...

Silicon Powder-Based Wafers for Low-Cost Photovoltaics: Laser Treatments and Nanowire Etching

In this study, laser-treated polycrystalline Si (pc-Si) wafers, fabricated by wire sawing of hot-pressed ingots sintered from Si powder, have been investigated. As-cut wafers and those with high-quality thin Si layers deposited on top of them by e-beam have been subjected to laser irradiation to clarify typical trends of structural modifications caused by laser treatments...

Electrogenerated chemiluminescence of violanthrone in dimethyl sulfoxide

Violanthrone is an anthraquinone vat dye, which is resistant to photochemical damage. Most previous work has concentrated on its chemiluminescence properties. In this report, electrogenerated chemiluminescence (ECL) of violanthrone has been investigated in dimethyl sulfoxide with 0.1M of tetraethylammonium bromide as electrolyte. Violanthrone luminesces in the potential range...

Thermally irreversible photochromic dithienylethenes

A lot of previously unknown derivatives of dithienylperfluorocyclopentene (DTPFCP) were synthesized. It was shown that 2,2′-dialkylsubstituted DTPFCP'S are phtochromes. The quantum yields of forward and backward photochemical reactions and spectral parameters of open and cyclic forms of the photochromes synthesized were measured. An attempt to obtain fluorescing phtochromes by...

Photo-induced processes in heterogeneous nanosystems. From photoexcitation to interfacial chemical transformations

This article briefly reviews some of our recent work carried out both from an experimental point of view as well as from a theoretical perspective to gain further understanding of the events that take place in Heterogeneous Photocatalysis. Previously, the multitude of reports from our laboratory and from many others looked at the primary photocatalytic events as involving (a...

Photochemical reactivity of zinc tetraphenylporphyrin induced by nonstoichiometric CdS nanoparticles in 2-propanol

The photoreactivity of zinc tetraphenylporphyrin (ZnTPP) in the presence of photoexcited CdS nanoparticles and molecular oxygen in 2-propanol has been revisited. The photodecomposition of ZnTPP in 2-propanol, in the presence of CdS(e-CB/h

Comparison of the photoactivities of two commercial titanium dioxide powders in the degradation of 1,4-dioxane

Two different commercial photocatalysts, Degussa P25 and Hombikat UV 100, were used to degrade 1,4-dioxane photocatalytically in an annular slurry photoreactor. The optimum photocatalyst loading for Degussa P25 was found to be 1.5 g L-1 while for Hombikat UV 100 was between 3.0−4.0 g L-1. The photoactivity of Degussa P25 is higher than that of Hombikat at lower photocatalyst...

Photocatalytic oxidation of fuel oxygenated additives in aqueous solutions

Experimental research of photocatalytical oxidation (PCO) of aqueous solutions of de-icing agents (ethylene glycol and ethylene glycol monoethyl ether) and methyl tert-butyl ether (MTBE) was undertaken. These chemicals are water-soluble components of jet and motor fuels accidentally disposed to the environment. Titanium dioxide (Degussa P25) under near-UV irradiation was selected...

Photoelectrochemical properties of sol-gel and particulate TiO2 layers

Polarization curves on irradiated TiO2 layers were measured in various electrolytes, namely sodium hydroxide, sulphuric acid, oxalic acid and potassium oxalate. Photocurrents measured in 0.1M NaOH are very small and decrease with increasing number of Degussa P25 TiO2 layers. Photocurrents for sol-gel TiO2 layers in 0.1M NaOH are about five times higher than for P25 TiO2 layers...

Methodologies and formalisms of resonance energy transfer in biophysics. Application to membrane model systems

The formalisms of resonance energy transfer (RET) to a distribution of acceptors are reviewed for several geometries relevant to membranes (planar, bilayer, multilayer) and random probe distribution. Models for nonrandom probe distribution (mean concentration model, phase separation model) are presented. Selected examples of quantitative applications of RET to these systems are...

Laboratory-scale photomineralisation of n-alkanes in aqueous solution, by photocatalytic membranes immobilising titanium dioxide

Kinetics of photocatalytic oxidation of methane, ethane, n-heptane, n-decane, and n-dodecane, to yield intermediates, and photomineralisation of intermediates, to yield carbon dioxide and water, was studied in aqueous solution, by a laboratory-scale photoreactor and photocatalytic membranes immobilizing 30±3 wt.% of TiO2, in the presence of stoichiometric hydrogen peroxide as...

Effects of pilot-plant photochemical pre-treatment (UV/H2O2) on the biodegradability of aqueous linear alkylbenzene sulfonate (LAS)

The effects of the photochemical pre-treatment by using a pilot-plant UV/H2O2 process on the biodegradability of aqueous linear alkylbenzene sulfonate (LAS) were studied. It was observed that the photochemical pre-treatment of the LAS solutions by UV-254/H2O2 increased the biodegradability of LAS solutions. Aqueous solutions with higher concentrations of LAS (> 100 mg/L) were non...

On the absorption and emission properties of three new non-steroidal anti-inflammatory drugs-β-cyclodextrin host-guest inclusion complexes: differentiated sensitivity to the microenvironment upon light excitation

The effects of β-cyclodextrin (β-CD) complexation on the absorption and emission properties of the non-steroidal anti-inflammatory drugs tolmetin (TM), diflunisal (DF), and fenbufen (FB) have been investigated. The absorption spectra of all these compounds are only slightly affected by the addition of β-CD. In contrast, the emission properties were markedly influenced by CD...

Photooxidation of sulfide, thiol, phenols, and cyclopentadiene by artificial light and solar light irradiation

The photooxidations of the toxic products sulfide, 2-mercaptoethanol and phenols under partial mineralisation in aqueous alkaline solution and the photooxidation of cyclopentadiene in ethanol in order to produce fine chemicals is described. Because the employed photosensitizers such as metal phthalocyanines, a tetraphenylporphyrine, rose bengal or methylene blue absorb in the...

Magnetorheological photocatalytic systems

Preparation and properties of a novel photocatalytic system containing magnetic cores coated with subsequently applied silica and titania shells are discussed. The underlying idea is to impart magnetic properties to the semiconductor particles that permits to control the rheological properties of the photocatalyst dispersion and makes possible its separation from treated solution...

Hydrogen evolution from water using CdS as photosensitizer

Colloidal chemical approaches are increasingly utilised for the preparation and stabilization of semiconductor nanoparticles.

Destruction of chlorinated pesticides in TiO2-enhanced photochemical process

Aqueous solutions containing 200mg/dm3 of lindane, p,p´-DDT and methoxychlor were photodegraded for 60 min in UV/TiO2/O2 system. Sparged air was introduced into the reactor environment. Titanium dioxide supported on glass, hollow microsphers served as the photocatalyst. Pesticides destruction ratio was evaluated and oxidation products were identificated by gas chromatography with...

Thin film solar cells on glass by transfer of monocrystalline Si films

Thin film solar cells based on monocrystalline Si films are transferred to a glass superstrate. Chemical vapor deposition serves to epitaxially deposit Si on quasi-monocrystalline Si films obtained from thermal crystallization of a double layer porous Si film on a Si wafer. A separation layer that forms during this crystallization process allows one to separate the epitaxial...

Time-resolved reflectivity technique: improvement and applications

A new method for determination of the reflectivity of Si in different phase transitions during pulsed laser irradiation is presented in this paper. This method is applied on TRR spectra of crystalline silicon (c-Si) in a medium of oxygen and amorphous hydrogenated silicon (a-Si: H). Time resolved reflectivity (TRR) measurements on silicon has been made during pulsed XeCl excimer...

Recombination mechanisms in crystalline silicon: bulk and surface contributions

In the present paper the most interesting results of a work on the influence of some processes used in the fabrication of microstructures on the bulk and surface electrical activity of the Si substrate are reported. In these studies the minority carrier lifetime and the surface recombination velocity were used as sensors of the Si electrical activity changes. Other electrical...

Series resistance effect on the output parameters of buried emitter silicon solar cells

A realistic distributed equivalent circuit for the buried emitter silicon solar cell is presented taking into consideration the carriers paths through the planar and vertical junctions. In addition, a new theoretical model for the cell characteristics including the cell's mismatching, series resistance, different junctions (planar and vertical) and junctions geometry is...