Dye Sensitized Solar cell

 Adsorption characteristics as well as Photophysical and photovoltaic properties of symmetrically substituted  phthalocyanine (Pc) with S-bridged 4-mercaptobenzoic acid (4-mercapto-Ba)-MPc where M is a chelated metal ion situated in the center of the inner cavity of the Pc macrocycle have been investigated. The metal has been taken to be Fe (II), Co (II), Ni (II), Cu (II) and Zn (II). Molecular dynamics simulation was employed to determine the adsorption behavior of  these metallo-phthalocyanine based dyes on the (101) surface of TiO2 anatase through the use of the Adsorption Locator code implemented in Accelrys Material studio software. The adsorption energy, rigid adsorption energy and deformation energy has been calculated. The adsorption energy values were negative, which indicates that adsorption could occur spontaneously. Also, DFT calculations of the optimum geometries as well as TD-DFT calculations of vertical excitation energies at the theory levels CAM-B3LYP/LANL2DZ and M06L/LANL2DZ have been performed for these studied dyes. The free energy change of injection  , the light harvesting efficiency (LHE) and the open circuit potential (eVoc) for the possible use of these dyes as sensitizers in DSSCs applications  have been also calculated. A reasonable charge transfer character was found for the HOMO → LUMO electronic transition which dominates the So→S1 vertical excitation in these systems. The nature of this intramolecular charge transfer electronic transition has been studied through the calculations of different descriptors namely, the amount of charge transferred and charge transfer distance  . The results of the present computations are reported and discussed. 

Titanium butoxide (Ti(OBu)4) precursor was used to prepare titanium dioxide (TiO2) nanorods as a photoanode by hydrothermal method directly on FTO glass with different hydrochloric acid (HCl) – water (H2O) ratio (12.5-7.5, 10-10, 7.5-12.5 and 5-15) ml and etching times (24, 48, and 72)h. The (XRD) results show good crystallinity of TiO2 with rutile phase and preferred orientations (101) and (002) for all samples. The grain size of the TiO2 nanorods increases with decrease the HCl concentration. The (FESEM) images show that an increase in HCl concentration leads to an increase in the rod diameter of the TiO2 NRs and a decrease in their length. The optimum efficiency (η) of DSSC based on TiO2 NRs was 3.255% at sample ET, where the preparation condition (7.5 ml HCl + 12.5 H2O) with a 48 h etching time.

Plasmonic nanoparticles are promising ways for the efficiency enhancement of thinfilm solar cells. We have taken into account the bare silicon wafer and the embedded thin-film silicon solar cells with Au nanodiscs array. We study these geometries of thin-film silicon solar cells and find the effect of Au nanoparticles on light transmission and reflection spectrum, power absorption, generation rate, power electric, and short-circuit current density; and for this, we have used finite difference time domain, FDTD software. We also consider the near-field electric intensity in the vicinity of nanoparticles with different sizes, which are known as a solar cells efficiency enhancement mechanism. Our study can be useful for new perspectives for antireflection coating applications and light management in silicon solar cells.

Two novel "spider-shaped" porphyrins, meso-tetraaryl-substituted 1PV-Por and zinc-metalated 1PV-Zn-Por, bearing four oligo(p-phenylenevinylene) (oPPV) pyridyl groups with long dodecyloxy chains on the phenyl groups, have been synthesized. The presence of four pyridyl groups in both porphyrins, which allow them to act as anchoring groups upon coordination to various Lewis acid sites, the conjugated oPPV bridges, which offer the possibility of electronic communication between the porphyrin core and the pyridyl groups, and the dodecyloxy groups, which offer the advantage of high solubility in a variety of organic solvents of different polarities and could prevent porphyrin aggregation, renders porphyrins 1PV-Por and 1PV-Zn-Por very promising sensitizers for dye-sensitized solar cells (DSSCs). Photophysical measurements, together with electrochemistry experiments and density functional theory calculations, suggest that both porphyrins have frontier molecular orbital energy lev...

Background Metal oxide nanoparticles (NPs) are becoming valuable due to their novel applications. The green synthesis of TiO2 NPs is more popular as a flexible and eco-friendly method compared to traditional chemical synthesis methods. TiO2 NPs are the most commonly used semiconductor in dye-sensitized solar cells (DSSCs). Results The biogenic TiO2 NPs were produced extracellularly by the marine halophilic bacterium Halomonas sp. RAM2. Response surface methodology (RSM) was used to optimize the biosynthesis process, resulting in a starting TiO2 concentration of 0.031 M and a pH of 5 for 92 min (⁓15 nm). TiO2 NPs were well-characterized after the calcination process at different temperatures of 500, 600, 700 and 800 °C. Anatase TiO2 NPs (calcined at 500 °C) with a smaller surface area and a wider bandgap were nominated for use in natural dye-sensitized solar cells (NDSSCs). The natural dye used as a photosensitizer is a mixture of three carotenoids extracted from the marine bacterium...

In this research, ZnO nanoparticles were synthesized at different pH values (3, 6 and 9) by using solvothermal method. To our knowledge, dye sensitized solar cells were fabricated using natural dyes extracted from henna (Lawsonia Inermis) based on ZnO nanoparticle as photoanode at various pH values. Synthesized ZnO samples were characterized using XRay Diffraction (XRD), Field Emission Scanning Electron Microscope (FESEM) with Energy Dispersive X-ray Spectroscopy (EDX), UV-Visible Spectroscopy and Fourier Transmission Infra-Red Spectroscopy (FTIR) and absorbance and transmittance properties of the prepared samples were investigated. The ZnO at pH 9 was obtained highest efficiency extracted from henna (Lawsonia Inermis) of 0.39% better than the other solar cells of pH variations.

The quest for cost effective and efficient solid-state electrolytes is a primary goal for dye sensitized solar cells (DSSCs). The present study describes an experimental approach of synthesizing simple composite electrolytes from iodide-triiodide ions (I−/I3−) incorporated into a polyaniline/thiourea matrix for solid-state DSSC applications. This electrolyte composition can be effectively used to decrease the probability of recombination at the TiO2/electrolyte interface and increase the catalytic process of I3− reduction at the electrolyte/counter electrode interface. The application of the optimized electrolyte in DSSC results in increased open-circuit voltage as well as short circuit current density, thereby increasing the overall efficiency by 73% as compared to the reference electrolyte. The present composition can prove to be a promising redox medium for solid state DSSCs.

Laser dye Rhodamine 6G (R6G) was incorporated in Poly MethyleMetha Acrylate (PMMA) polymer at different particles density from zinc oxide (ZnO) as (nanowire, nanoflower) synthesized using the hydrothermal method as random laser active medium. The thickness and emission spectra of the films were characterized by Scanning Electron Microscopy (SEM) and Fluorescence spectrum. The optimum results at the Width Half-Maximum (FWHM) are about (13, 11) nm for both ZnO wires and flower respectively at high pumping energy equal (20, 16) mJ respectively with optimum concentrations are 10-4mol/l .While Amplified Spontaneous Emission (ASE) was observe at low pumping intensity using Second Harmonic Generation(SHG) Nd-YAG pulse laser working at wavelength 532 nm. The homogeneous thickness of the films equal (14.6 –15) μm was used. Finally, the performances of ZnO random laser active medium for both shapes (wires and flowers) are determined via the relationship between the emission line and FWHM. Fro...

Two fused‐thiophene‐containing ruthenium sensitizers, [Ru(Hdcbpy)(ottip)(NCS)2]–·0.5[H]+·0.5[N(C4H9)4]+ [Z1, H2dcbpy = 4,4′‐dicarboxy‐2,2′‐bipyridine, ottip = 2‐(5‐octylthieno[3,2‐b]thiophen‐2‐yl)‐1H‐imidazo[4,5‐f][1,10]phenanthroline] and [Ru(Hdcbpy)(odttip)(NCS)2]–·0.5[H]+·0.5[N(C4H9)4]+ {Z2, odttip = 2‐[6‐octyldithieno(3,2‐b:2′,3′)thiophen‐2‐yl]‐1H‐imidazo[4,5‐f][1,10]phenanthroline}, were designed for use in dye‐sensitized solar cell (DSSC) applications. The fused‐thiophene‐based Z1 and Z2 have stronger light‐harvesting capabilities compared with a non‐fused‐thiophene analog, [Ru(Hdcbpy)(otip)(NCS)2]–·0.5[H]+·0.5[N(C4H9)4]+ [JF‐2t, otip = 2‐(5‐octylthiophen‐2‐yl)‐1H‐imidazo[4,5‐f][1,10]phenanthroline], and a standard N3 dye. The power‐conversion efficiency of the Z1‐ and Z2‐sensitized solar cells were superior (8.70 % and 8.15 %) to JF‐2t‐ and N3‐sensitized solar cells (7.85 and 7.40 %, respectively) under standard AM1.5G full sunlight irradiation. The photovoltaic performance o...

In nature, solar energy is captured by different types of light harvesting protein–pigment complexes. Two of these photoactivatable proteins are bacteriorhodopsin (bR), which utilizes a retinal moiety to function as a proton pump, and photosystem I (PSI), which uses a chlorophyll antenna to catalyze unidirectional electron transfer. Both PSI and bR are well characterized biochemically and have been integrated into solar photovoltaic (PV) devices built from sustainable materials. Both PSI and bR are some of the best performing photosensitizers in the bio-sensitized PV field, yet relatively little attention has been devoted to the development of more sustainable, biocompatible alternative counter electrodes and electrolytes for bio-sensitized solar cells. Careful selection of the electrolyte and counter electrode components is critical to designing bio-sensitized solar cells with more sustainable materials and improved device performance. This work explores the use of poly (3,4-ethyle...

In this study, titanium oxide nanotubes anodized on three different surface morphologies of titanium foils, were investigated. AFM images is used to show different surface roughness of these foils. Nanotubes were anodized on titanium foils with 1) no polishing process (A sample), 2) electropolishing process (B sample) and 3) electropolishing process in ethanolic electrolyte (C sample). To study the ordering of titanium oxide nanotubes, the FE-SEM images of nanotubes backside were investigated. It can be seen that by decreasing surface roughness, the distribution of nanotubes diameter size becomes more uniform significantly and thereby highly ordering of nanotubes can be observed.