Application In Dye-sensitized Solar Cells Research Articles

Dft, Dftb and Td-Dft Theoretical Investigations of Π-Conjugated Molecules Based on Thieno[2,3-B] Indole for Dye-Sensitized Solar Cell Applications

Dft, Dftb and Td-Dft Theoretical Investigations of Π-Conjugated Molecules Based on Thieno[2,3-B] Indole for Dye-Sensitized Solar Cell Applications

Electrochemical Properties of Natural Sensitizer from Garcinia mangostana and Archidendron pauciflorum Pericarps for Dye-Sensitized Solar Cell (DSSC) Application

Dye-sensitized solar cells (DSSC) create imitation photosynthesis by using chemical reactions to produce electricity from sunlight. DSSC has been pursued in numerous studies due to its capability to achieve efficiencies of up to 15% with artificial photosensitizer in diffuse light. However, artificial photosensitizers present a limitation because of the complex processing of metal compound. Therefore, various types of sensitizers were developed and synthesized to surpass the artificial sensitizer performances such as natural sensitizers from bio-based materials including plants, due to simple processing techniques and low environmental impact. Thus, this study examines the potential and properties of natural sensitizers from the waste of bio-based materials from Garcinia mangostana (mangosteen fruit) and Archidendron pauciflorum (jering fruit). Both fruits pericarps have dark color pigments as dark purple and dark brown, respectively, which promise a good absorption and has potential to be used as sensitizer for DSSC. Each pericarps dye extracted using cold extraction method in methanol solvent. Electrochemical properties and photovoltaic properties of the natural photosensitizers were studied. The highest peaks of photoluminescence spectra of mangosteen and jering sensitizers were at 490 and 670 nm, respectively, due to their different types of dye pigment extracted. We also obtained the absorption spectra for both mangosteen and jering sensitizers at 380-500 and 400-600 nm, respectively, in blue shift behavior. The redox reaction was also studied using cyclic voltammetry and identify their energy levels. The DSSC device with mangosteen sensitizer achieved an efficiency of 0.38% with 35.43% (IPCE at 337 nm) and 37.75 Ω (Rs), whereas that with jering sensitizer has efficiency of 0.07% with 25.31% (IPCE at 337 nm) and 490.70 Ω (Rs). Performance studies for both photosensitizers were weak due to their HOMO-LUMO levels, but the results show that both natural dyes can be potentially applied as photosensitizer in DSSC.

Molecular Engineering of Indoline Dyes and Their Application in Dye-Sensitized Solar Cells: Effect of Planarity and Side Chain on Interfacial Charge-Transfer Processes

Interfacial charge-transfer is the critical process during the operation of dye-sensitized solar cells, determining the photovoltaic performance of the cell. Interfacial charge-transfer processes a...

Experimental and first-principles study of a new hydrazine derivative for DSSC applications

Hydrazine derivatives have a wide variety of applications in organic synthesis, material science, medical treatments, as well as the dye-sensitized solar cells (DSSC). In this work, the molecular structure, electronic spectra and first principles investigation for the exo-endo isomerization in (1E,2E)-bis[1-(4-nitrophenyl)ethylidene]hydrazine were studied. The structural interactions and synthon formations have been determined experimentally via Hirshfeld surface analysis (HSA) and two-dimensional fingerprint plots (2D-FP). Furthermore, the solid-state XRD/HSA interactions have been used to explain the physical behavior of the compound. The transition state for the exo-endo isomerization was located using density functional theory (DFT). The activation barrier is estimated to be 110.5 kJ/mol (in vacuo). The endo isomer was found to be slightly more stable than the exo one. The UV-Vis spectra of the two isomers were obtained using time-dependent density functional theory (TDDFT) and compared to the experimental spectra in vacuo, water, and methanol. To explore the potential of the new compound as a DSSC sensitizer, the emission spectrum was also constructed by optimizing the singlet electronic excited state.

Long-Term Stability Improvement of Non-Toxic Dye-Sensitized Solar Cells via Poly(ethylene oxide) Gel Electrolytes for Future Textile-Based Solar Cells.

To overcome the long-term stability problems of dye-sensitized solar cells (DSSC) due to solvent evaporation and leakage, gelling the electrolyte with polymers is an appropriate option. Especially for future applications of textile-based DSSCs, which require cost-effective and environmentally friendly materials, such an improvement of the electrolyte is necessary. Therefore, the temporal progressions of efficiencies and fill factors of non-toxic glass-based DSSCs resulting from different gel electrolytes with poly(ethylene oxide) (PEO) are investigated over 52 days comparatively. Dimethyl sulfoxide (DMSO) proved to be a suitable non-toxic solvent for the proposed gel electrolyte without ionic liquids. A PEO concentration of 17.4 wt% resulted in an optimal compromise with a relatively high efficiency over the entire period. Lower concentrations resulted in higher efficiencies during the first days but in a poorer long-term stability, whereas a higher PEO concentration resulted in an overall lower efficiency. Solvent remaining in the gel electrolyte during application was found advantageous compared to previous solvent evaporation. In contrast to a commercial liquid electrolyte, the long-term stability regarding the efficiency was improved successfully with a similar fill factor and thus equal quality.

Facile synthesis of gold and platinum doped titanium oxide nanoparticles for antibacterial and photocatalytic activity: A photodynamic approach.

A simple method has been needed to synthesize nanoparticles (NPs) to avoid environmental pollution, an alternative chemical and physical method. This current study deals with phytosynthesis of gold (Au) and platinum (Pt) metal doped with titanium oxide (TiO2) NPs using Enterolobium saman bark extract. This extract plays a vital role in reducing and stabilizing Au and Pt doped into the TiO2 NPs lattices. Phytosynthesized samples were characterized by XRD, SEM, ED-XRF, TEM, FTIR, Raman, and UV-vis-DRS analyses. The metal doping effect has decreased bandgap energy and particle size, whereas increased conductivity for TiO2/M-Au and TiO2/M-Pt NPs compared to pristine TiO2 NPs. Phytosynthesized NPs were fabricated for dye-sensitized solar cell (DSSC) and photocatalytic behaviour against methylene blue (MB) dye was studied. An obtained result demonstrates that TiO2/M-Au NPs have excellent feasibility for applying DSSC and photocatalytic application due to particle size, crystallite size, absorption ability, and bandgap energy. Besides, synthesized samples were measured with cyclic voltammetry and impedance spectroscopy found that the metal doping is drifted the dielectric and increases that the metal doping is drifted the dielectric increases electro-catalytic of the TiO2. Different concentrations of all NPs were tested against Escherichia coli MTCC 40 and S. aureus ATCC 6633 bacteria by a well-diffusion method. The 10 mg concentration of all NPs showed better antibacterial activity. However, we believe that the proposed simple phytosynthesized method provides an efficient way to overcome the chemical and physical methods.

Porphyrin sensitizers with acceptor structural engineering for dye-sensitized solar cells

Two porphyrin-based sensitizers, SGT-028 and SGT-029, were designed and synthesized via acceptor engineering for application in dye-sensitized solar cells (DSSCs). Porphyrin SGT-028 was designed by introducing a salicylic acid anchoring group instead of a conventional benzoic acid in the platform of donor-porphyrin-triple bond-BTD-phenyl-acceptor sensitizers (e.g., SGT-021 and SM315). As for SGT-029, an additional alkylated benzothiadiazole (BTD) unit was substituted to the BTD of D-π-A porphyrin sensitizers. The impact of the anchoring group and long alkyl chains on the optical character, electrochemical property, and photovoltaic performance were studied and also compared with a reference dye of SGT-021, which had previously been synthesized by our group. As a result, both of these two porphyrin sensitizers obtained a similar absorption range and energy band gap to SGT-021 dye. After performing optimization of DSSC devices, SGT-029 achieved a comparatively high power conversion efficiency (PCE) of 10.5%, but was inferior to the benchmark porphyrin sensitizer SGT-021 (12.7%), and a slightly lower PCE of 9.1% was exhibited by SGT-028, under the standard AM 1.5G light intensity. It is worth mentioning that the PCE of 12.7% is the highest efficiency for a SGT-021-based device up to now. The main reason was supposed to be the dye adsorption amount difference, maybe allowing for a serious dye aggregation, which often leads to an increased quenching of excited states and limits the charge injection into the TiO2 semiconductor substrate, and lower light harvest efficiency (LHE), resulting in lower photocurrent, photovoltage, and PCE.

Performance of P. betle extraction as sensitizer in dye-sensitized solar cells (DSSCs)

Natural dyes extracted from Piper betle (P. betle) pigment, was utilized and researched as sensitizer in DSSCs application. The optical characteristics of the extracted dye and photovoltaic performance of the cells were studied. The extracts showed UV-vis absorptions in the range of 530–560 nm with broad maxima absorption at∼ 430 nm. For P. betle the photovoltaic performance of the sample with 3.16μm-thick ZnO produced the best results with open-circuit voltage (VOC), short-circuit current density (JSC), fill factor (FF), and energy conversion efficiency (η) values of 0.33 V, 6.35 mA/cm2, 0.52, and 1.09%, respectively.

Study of Beta vulgaris (Beetroot) Extraction in Polar Solvents as Photoabsorber in Dye-Sensitized Solar Cells Application

Over the last two centuries, energy needs have increased substantially until non-renewable resources nearly come to depletion. Therefore, the application of renewable energy resources like solar energy is absolutely appointed favorable due to its economical impact and improved technology. Dye-sensitized solar cell (DSSC) being the type of solar cell that utilize dye as light sensitizer for the operation and become the best alternative rather than toxic chemical dyes. Betalains is one of the pigment of natural dyes that can be extracted from fruit and vegetables which majorly available in beetroot (Beta vulgaris). To get the pigment for solar cell application, the optimum extraction is crucial. Hence, in this study, several polar solvents such as distilled water, methanol, ethanol, isopropanol, n-butanol, formic acid and acetic acid were used to extract betalain pigment from Beta vulgaris (BV). Then, several characterizations were carried out to analyze the photoabsorber properties using Ultraviolet-visible Spectroscopy (UV-Vis), Fourier-Transform Infrared Spectroscopy (FTIR), High Performance Liquid Chromatography (HPLC) and Scanning Electron Microscopy (SEM). The energy bandgap of BV in different solvents (ITO/TiO2/BV) are 2.19, 2.35, 2.65, 2.73, 2.78, 2.98 and 3.00 eV for methanol, n-butanol, formic acid, ethanol, acetic acid, water and isopropanol respectively. Whilst, FTIR spectrum shows the presence of functional group of O-H, C=O and C-O-C and HPLC analysis depicted the existence of betacyanin pigment all in samples. SEM images show the presence of porous structure of TiO2 and irregular pits formed due to the formation of BV layer on TiO2. In conclusion, overall findings suggested that methanol is the best solvent for extraction of betalain pigment, answering it has best photoabsorber properties among the sample series. Further detailed study is recommended to maximise the potential of Beta vulgaris pigment as photoabsorber in DSSC application.

Novel cost-effective and electrocatalytically active intermetallic nickel aluminide counter electrode for dye sensitized solar cells

The very high cost, scarcity and dissolubility of platinum (Pt) is the center of debates as a counter electrode (CE) in dye sensitized solar cells (DSSCs) research domain. To deal with such core issues, herein, novel low-cost and electro-catalytically active inter-metallic nickel aluminide (Ni3Al) thin films have been fabricated successfully on fluorine-doped tin oxide substrates by DC magnetron sputtering at room temperature. For the first time, Ni3Al has been utilized as a CE for DSSCs application. Further, the solar cell performance of Ni3Al based DSSC has compared with the sputtered coated Pt thin film based DSSC performance. Under open atmospheric experimental preparation conditions (in air), a maximum power conversion efficiency of 3% has been achieved with Ni3Al CE. The obtained efficiency is quite analogous to a DSSC fabricated with a Pt CE. Further, as-fabricated Ni3Al CEs have exhibited better electrochemical catalytic activity and anti-corrosion effect than that of sputtered Pt CEs. The low-cost and excellent electrocatalytic properties of intermetallic Ni3Al thin films may pave the way towards development of Pt-free CE for DSSCs.

Modern third generation solar photovoltaic technology: Dye sensitized solar cell

Depleting conventional energy resources are forcing the world to search for new and renewable energy resources. Solar energy is one of the potent and abundant energy resource .To use the solar energy to its fullest along with conventional technology has specific limitations. These limitations can be eliminated by use of Dye Sensitized Solar Cell (DSSC). DSSC can be seen as promising future technology. It is advantageous over Silicon (Si) based Photovoltaic (PV) cell in terms cost, easy manufacturing, stability at higher temperature, aesthetics, etc. Also it works in indoor conditions i.e. diffused sunlight which nearly not feasible with conventional PV cells. Now Research and Development Departments of many countries like Japan, Germany, USA, Switzerland, India, China and many firms like G-Cell, Oxford PV, Sony, TATA-Dyesol are working on DSSC to improve its various aspects so as to make it more applicable in various conditions. The paper will discuss the concept, construction, working of DSSC. Also it will illustrate current applications of DSSC.

Experimental and theoretical study of the synthesis of N-doped TiO2 by N ion implantation of TiO2 thin films

Since major limitations of the Dye-Sensitized Solar Cells (DSSCs) efficiency are assumed to come from (i) the low resistivity of the generally used TiO2 (ρ = 1 Ω·cm) and (ii) the undesired electron-hole recombination at the semiconductor/dye-electrolyte interfaces, the development of N-doped TiO2 semiconductor (TiO2:N) has attracted considerable interest. However, the synthesis of this material still remains a challenge as it is difficult to monitor (i) the doping level and (ii) the position of the nitrogen atoms into the titanium oxide lattice. In this context, the combination of Reactive Magnetron Sputtering (RMS) and Ion implantation (II) recently allowed to finely control the nitrogen chemistry of N-doped TiO2 materials. However, the structural properties, such as the crystalline constitution and morphology of the implanted materials are of crucial interest for the intended application. Therefore, we performed a parametric study of the ion beam parameters on the physical and chemical properties of TiO2:N in the aim of charge transport application in DSSCs and the results were supplemented by a simulation tool (i.e. TRIDYN software), allowing to distinguish this work from the others. Briefly, we observed that the sputtering of the ion implanted layer prevails with low accelerating voltages while the ion implantation process and its intrinsic effects are observed for high accelerating voltage conditions. We also demonstrated that the sputtering effect issue can be quite easily avoided for low dose conditions.

Carbazole-substituted dialkoxybenzodithiophene dyes for efficient light harvesting and the effect of alkoxy tail length

A set of new donor-π-acceptor organic PM dyes, bearing carbazole as electron donor and cyanoacrylic acid as electron acceptor, has been synthesized and fully characterized with particular focus on application in dye-sensitized solar cells (DSSCs). Importantly, a change in ‘linker’ structure resulted in the electron re-distribution in the oxidized dye, in general, and the localization of the ‘electron hole’, in particular, when compared with the MK2 benchmark. In addition, modifying the PM dyes with different lengths of alkoxy chains, that is, 1, 4, and 8 carbons, strongly influences the access of the oxidized cobalt ions to the surface affecting recombination, which had an appreciable effect on dye-sensitized solar cell performances. While the performance of the PM dyes was 15–20% lower than MK2, they are considerably easier and less expensive to synthesize, offering excellent potential for future DSSC applications.

Design and fabrication of WSe2/CNTs hybrid network: A highly efficient and stable electrodes for dye sensitized solar cells (DSSCs)

This study presents a rational-designed structure and facile strategy to fabricate tungsten selenide/carbon nanotube (WSe2/CNT) hybrid photoanodes as promising anodes for DSSC applications. The fundamental physic-chemical properties proved that the uniform, pure and tubular WSe2/CNT hybrid nanoparticles were produced and WSe2 nanoparticles were anchored the CNT surface successfully. The WSe2/CNT hybrid nanostructure exhibits higher surface area (107.8 m2/g) and pore size (45.3 nm) than compared with pure WSe2 (86.2 m2/g and 19.8 nm). WSe2/CNT composite exhibits enhanced photo-conversion efficiency (8.85%), electro-catalytic activity and high electron life time (87 ns). The improved PCE of the WSe2/CNT composite is due to the CNTs can reduce electron-hole pair recombination and efficiently inhibit the aggregation of WSe2 for fully exposing the active edges. Those outstanding electrochemical performances of WSe2/CNT hybrid can be assigned to its unique nanoarchitecture: the CNT with high conductivity work as the skeleton of WSe2/CNT anode facilitating the electron transfer; the CNT can effectively prevent WSe2 from the aggregation and promote the in-situ growth of WSe2 on CNT. Moreover, the hybrid structure, which can allow for efficient ionic diffusion and easy electrolyte infiltration.

In situ synthesis of ZnFe2O4 rough nanospheres on carbon nanofibers as an efficient titanium mesh substrate counter electrode for triiodide reduction in dye-sensitized solar cells

There is no doubt that counter electrode (CE) plays a vital role in dye-sensitized solar cells (DSSCs). Herein, Zinc Ferrite/carbon nanofibers (ZnFe2O4/CNFs) composite is successfully fabricated by electrospinning and hydrothermal method and coated on titanium (Ti) mesh as an efficient CE material, which is further applied to DSSCs. The Ti mesh has been done as conductive substrate to make the DSSCs have smaller transmission resistance, great stability and sustainable utilization. Via repeated measurements, the ZnFe2O4/CNFs CE which is prepared on Ti mesh exhibits good power conversion efficiency (PCE) of 9.05%, which is higher than commercial Platinum (Pt) fluorine-doped tin oxide (FTO) CE (7.21%) and CNFs Ti mesh CE (7.80%) under the same conditions. Most interestingly, the CNFs CE that prepared on Ti mesh has higher PCE than Pt CE, this is mainly due to the use of Ti mesh which is more conducive to the interface transport of iodine ion and electron transfer rate. All of these results indicate that ZnFe2O4/CNFs composite Ti mesh CE has high electrochemical performance and can be favorable for low-cost efficient DSSCs application.

Morphology-controlled fabrication of NiCo2S4 nanostructures decorating carbon nanofibers as low-cost counter electrode for efficient dye-sensitized solar cells

The development of highly efficient, earth-abundant and low-cost counter electrode materials is of significant importance and challenge for practical application in dye-sensitized solar cells. In this work, morphology-controlled NiCo2S4 nanoparticles (NPs) and nanorods (NRs) decorating carbon nanofibers (CNFs) have been prepared via an electrospinning and hydrothermal or solvothermal strategy, which are further utilized as counter electrodes (CEs) in dye-sensitized solar cells (DSSCs). Benefitting from the rich nickel and cobalt ions redox chemistry and more exposed catalytically active sites from NiCo2S4 NRs grown vertically on the surface of CNFs as well as faster electron transporting capability providing by the highly conductive CNFs, the DSSC device based on NiCo2S4 NRs/CNFs CE yields an excellent power conversion efficiency of 9.47%, which is higher than that of the devices with NiCo2S4 NPs/CNFs (8.63%), Pt (8.18%) and CNFs (6.06%) as CEs under AM 1.5 G irradiation. Furthermore, the NiCo2S4 NRs/CNFs CE shows an excellent electrochemical stability in an iodine-based electrolyte. This study highlights a controllable and versatile route to rational design efficient counter electrode catalysts for high-performance CEs application.

Synthesis and characterizations of sol–gel derived LaFeO3 perovskite powders

In this study, LaFeO3 perovskite powders were prepared via the sol–gel method in two different annealing temperatures (500 and 850 °C-according to DTA/TG results) for use in dye-sensitized solar cell applications. The thermal, structural, microstructural, particle size, optical and magnetic properties of the samples were characterized by differential thermal analysis (DTA)/thermogravimetric analysis (TG), Fourier transforms infrared spectrometer (FTIR), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), scanning electron microscope (SEM), particle size analysis (PSA), UV–Vis spectrometer and vibrating sample magnetometer (VSM). Our XRD findings show that the as-synthesized powders have an excellent crystallinity, and Scherrer’s Equation is used for the estimation of crystallite sizes (within 26–29 nm). Samples were analyzed to reveal the valence states of elements through XPS. Survey scan XPS spectra and high-resolution XPS spectra of La-3d5 and Fe-2p for LaFeO3 samples are given. SEMs employed to observe surface morphologies of all xerogel and ceramic perovskite powder materials and SEM images were verified with PSA results. UV–Vis spectrometer analysis results show that the optical bandgap values (Eg) as measured on both particles were found 2.42 eV. In addition to all analyses, the powders show ferromagnetic behavior, and VSM analyses are used to determine ferromagnetic properties. These results, especially low bandgap, make LaFeO3 powders possible to further increase the performance and efficiency of perovskite-based cells.

Preparation of Cu-doped ZnO nanoparticles via layered double hydroxide and application for dye-sensitized solar cells

It has been reported that doping ZnO with metal ions can alter the band gap and immensely enhance electron transport. In this regard, to increase the efficiency of cost-effective dye-sensitized solar cells (DSSCs), we synthesized Cu-doped ZnO nanocomposites from layered double hydroxide (LDH) precursors via a facile method. LDH layers were homogeneously doped with Cu ions, and mixed metal oxides (MMOs) were obtained after annealing. The morphology and optical and electrochemical properties of the as-synthesized Cu-doped ZnO nanocomposites were systematically studied. The introduction of Cu ions increases the specific surface area of ZnO and increases light absorption in the visible region. The Cu-doped ZnO MMOs were used as the photoanode of DSSCs, and the effect of the amount of the Cu dopant on the performance of the solar cells was studied. At the optimal doping weight percentage of Cu (0.25 wt%), the solar cell based on Cu-doped ZnO MMO and D149 dye achieved the highest short-circuit current of 7.12 mA cm−2 and the highest power conversion efficiency of 1.50%.

FT-IR and FT-RAMAN analysis and light-harvesting efficiency (LHE) enhancement for DSSC applications of hydrazide derivatives

The vibrational frequencies obtained by the recorded the spectra of FT-IR and FT-Raman are precisely assigned and compared with the theoretical frequencies. The stabilities of p-hydroxybenzoylhydrazine (HBH) and p-aminobenzoylhydrazide(ABH) are analyzed through PES scan, and most stable structures are obtained. On the most stable structures of these two compounds, the HOMO–LUMO analysis is carried out at B3LYP/6-31G (d,p) level for the zero field and with fields (0.015 and 0.025 VA−1). The HOMO–LUMO gap widely decreases from 4.0592 eV to 0.6323 eV and 3.7645 eV to 0.4040 eV, respectively, as the field increases (0.0—0.025 VA−1). The HOMO–LUMO gap is also measured from the DOS spectrum which is also in line along with the calculated value using the Gaussian 09 W program package. The DOS spectrum predicts that the HOMO–LUMO gap decreases when there is the increase in the electric field. The donors studied theoretically in this study are azulene, pyrrole, furan, tetrafuran and thiophene. The global reactivity descriptors, i.e., ionization potential (IP), hardness (η), chemical potential (μ), electron affinity (EA), softness (s), electronegativity (χ), electrophilicity index (ω), maximum amount of electronic charge (∆Nmax), nucleofugality (∆En), electrofugality (∆Ee) and ΔEback-donation are calculated for all hydrazide derivatives. The best dye sensitized solar cell (DSSC) performance is observed in HBH and ABH derivatives with thiophene donor group compared to other donor groups.

Coumarin-based D–π–A dyes for efficient DSSCs: DFT and TD-DFT study of the π-spacers influence on photovoltaic properties

A series of D–π–A architectures dyes with Coumarin-based derivatives as difluorenylaminocoumarin (DF) and diphenylaminocoumarin (DP) have been designed by modifying the π-bridge for potential application in dye-sensitized solar cells (DSSCs). Three different π-bridges viz. benzothiadiazole (BTD), diketopyrrolopyrrole (DPP) and quinoxaline (QX) with are used to design six different dye systems DFi (i = 1–3) on difluorenylaminocoumarin-thiophene-cyanoacrylic acid (R1) and DPi (i = 1–3) on diphenylaminocoumarin-thiophene-cyanoacrylic acid (R2). The electronic, optical and photovoltaic properties have been evaluated, using the density functional theory (DFT), and time dependant DFT methods to study the effect of these spacers on the cell performance. In addition, we have used four functionals to establish our calculation method, in order to compare the theoretical with the experimental results of R1 and R2 dyes. Thus, the CAM-B3LYP functional was sufficient to predict the UV–visible spectra. Moreover, the gap energy (Egap), Voc, the electronic injection free energy (ΔGinject), light harvesting efficiency (LHE), total reorganization energy (λtotal), and absorption spectra of all dyes were discussed. In addition the DF2, DP2 dyes are displayed smaller Egap, negative ΔGinject and absorption spectra shifted to red compared to R1 and R2, respectively. The results of these dyes reveal that the DF2 and DP2 dyes molecules are favourable candidates for DSSCs application.