Dyes For Dye-sensitized Solar Cells Research Articles

Theoretical exploration of copper based electrolytes for third generation dye sensitized solar cells

Dye-sensitized solar cells (DSSCs) present a promising avenue for addressing the escalating need for clean energy solutions. These innovative cells offer a sustainable approach to meet the rising demands for environmentally friendly power sources. An assessment was conducted on a copper complex containing a hexadentate ligand, serving as a redox shuttle, alongside triphenylamine-based organic dyes in the construction of DSSC. This study thoroughly investigates the electronic structures, FMO, MEP surfaces, and photophysical properties of copper redox shuttle and triphenylamine dyes employing DFT and TDDFT calculations. The copper system, [Cu(bpyPY4)]2+/+, analyzed in this study, is anchored by the hexadentate polypyridyl ligand bpyPY4 (6,6′-bis(1,1-di(pyridine-2-yl)ethyl)-2,2′-bipyridine), scrutinized as a redox shuttle (RS). The assessed redox potential for [Cu(bpyPY4)]2+/+ is −4.67 eV. This indicates that the dye can effectively undergo regeneration by transferring electrons from the reduced form of the redox shuttle to the oxidized form of the dye. The photovoltaic efficiency has been analyzed with regard to various factors, including the energy gap between the HOMO and LUMO, the excited-state oxidation potential (Edye*), electron injection ability (∆Ginj), electron regeneration (∆Greg), light harvesting efficiency, short-circuit current density (JSC) and the open-circuit voltage (Voc). This study sheds light on present-day developments and forthcoming prospects in utilizing 3d transition metal-based redox shuttles, presenting them as compelling candidates for integration with organic dyes in Dye-Sensitized Solar Cells (DSSCs). This integration holds promise for more efficient solar spectrum absorption and enhanced performance of solar devices.

Unlocking the potential of anthocyanin-based dye-sensitized solar cells: Strategies for enhancing efficiency, stability, and economic viability

This study investigates the feasibility and potential of anthocyanins as natural dyes in dye-sensitized solar cells (DSSCs). The focus is on the efficiency, stability, and economic viability of using anthocyanins as green alternatives in renewable energy technology. While anthocyanins offer controlled modification of optical properties at a low cost, there are challenges to overcome in achieving high efficiency, long-term stability, and commercial affordability. The study analyzes recent research developments and proposes strategies to enhance efficiency, stability, and economic viability. Optimization techniques, such as dye mixing and co-pigmentation, as well as modifications to dye structure and protective coatings, are explored. Economic considerations, availability, scalability, and innovative approaches like dye engineering and novel device architectures are discussed. The findings highlight the potential of anthocyanin-based DSSCs as a sustainable and economically viable solar energy technology. The study concludes with recommendations for future research to overcome challenges and advance the field of anthocyanin-based DSSCs.

Comparative study of natural and synthetic dyes in DSSCs: An experimental and computational approach

This study explores the natural and synthetic dyes as sensitizers for dye-sensitized solar cells (DSSCs). Anthocyanin dye extract (PG) from pomegranate (Punica granatum) fruit, betanin pigment (BR) from beetroot (Beta vulgaris), and the commercially available organic dye, Rose Bengal (RB), were investigated as sensitizers for DSSCs and their photovoltaic performances were recorded. Density functional theory (DFT) and time-dependent DFT (TD-DFT) studies have also been performed in order to get insight into the photophysical and photoelectrochemical properties. The overall efficiencies (η) of 0.34%, 0.30%, and 0.25% were obtained for the PG, BR, and RB dyes under 1 sun illumination, respectively. The results infer that PG dye would act as a promising photo-sensitizer for DSSCs as compared to BR and RB sensitizers, which may be due to better interaction between anthocyanin molecule of pomegranate extract and TiO2.

Effects of Several Auxiliary Acceptors and Anchoring Groups on Charge Transfer and Photophysical Properties of D-A-π-A Type DSSCs: A DFT Study.

In this paper, we performed theoretical studies on the twelve D-A-π-A type organic dyes (G-1 ~ G-3, M-1 ~ M-3, J-1 ~ J-3, and S-1 ~ S-3) with 9-phenylcarbazole as the electron donor in anticipation of the application of these dyes in dye-sensitized solar cells (DSSCs). DFT and TD-DFT methods are applied to investigate in detail the molecular geometries, frontier molecular orbitals (FMOs), absorption spectra, charge density difference (CDD), and transition density matrix (TDM) of several dyes. The results show that the M-series (M-1 ~ M-3) dyes have the largest dihedral angles between the electron donor and the auxiliary acceptor and also has the largest energy gaps in HOMO-LUMO orbitals, which greatly reduces the charge transfer efficiency. Finally, the UV-Vis absorption spectra inferred that the anchoring groups modified with o-nitrobenzoic acid (G-3, M-3, J-3, S-3) can red-shift the absorption peaks of the dyes, which results in higher light-harvesting efficiency and improves the power conversion efficiency of DSSCs. Overall, all of these dyes contribute to the improvement of photovoltaic power conversion efficiency and have potential for application in DSSCs devices.

DFT study of the spectroscopic behaviour of different iron(II)-terpyridine derivatives with application in DSSCs

Through a comprehensive computational analysis utilizing Density Functional Theory (DFT), we clarify the electronic structure and spectroscopic properties of modified iron(II)-terpyridine derivatives, with the aim of enhancing the efficiency of Dye-Sensitized Solar Cells (DSSCs). We optimized a series of nineteen iron(II)-terpyridine derivatives and related compounds in acetonitrile (MeCN) as the solvent using TDDFT, evaluating their potential as dyes for DSSCs. From the conducted computations on the optimized geometries of the nineteen [Fe(Ln)2]2+ complexes, containing substituted terpyridine and related ligands L1-L19, we determined the wavelengths (λ in nm), transition energy (E in eV), oscillator strength (f), type of transitions, excited state lifetime (τ), light harvesting efficiency (LHE), frontier orbital character and their energies (ELUMO/EHOMO), natural transition orbitals (NTOs), injection driving force of a dye (ΔGinject), and regeneration driving force of a dye (ΔGregenerate). Results show that the theoretically calculated values for assessing dye efficiency in a DSSC correlate with available experimental values. The UV–visible spectra of [Fe(Ln)2]2+ exhibited a peak above 500 nm (λmax) in the visible region, attributed to the ligand-to-metal charge transfer band (LMCT) in literature, and a significant absorbance peak at approximately 300 nm (λA,max) in the UV region. The M06-D3/CEP-121G method replicated all reported λmax and λA,max values with a mean absolute deviation (MAD) of 21 and 18 nm, respectively. Our findings underscore the connections between electronic modifications and absorption spectra, emphasizing their impact on the light-harvesting capabilities and overall performance of DSSCs. This research contributes to the advancement of fundamental principles governing the design and optimization of novel photovoltaic materials, facilitating the development of more efficient and sustainable solar energy technologies.

Studies on Natural Dyes Derived from Common Flowers

The use of natural materials for the synthesis of energy devices has been on a rise since last decade. In this regard, the use of natural dyes for application in dye sensitized solar cells (DSSC) is not only cost-effective but also beneficial for the environment in the long run. In this regard, natural dyes have been extracted from over ten flowers and their absorption characteristics have been studied. Additionally, a combination of few flowers according to their absorption spectrum was used as a natural dye in DSSC to assess its light harvesting capability. Although, the generated potential was poor, the device was able to generate reasonable current, of ∼ 100 µA.cm-2.

Application of machine learning-based read-across structure-property relationship (RASPR) as a new tool for predictive modelling: Prediction of power conversion efficiency (PCE) for selected classes of organic dyes in dye-sensitized solar cells (DSSCs).

The application of various in-silico-based approaches for the prediction of various properties of materials has been an effective alternative to experimental methods. Recently, the concepts of Quantitative structure-property relationship (QSPR) and read-across (RA) methods were merged to develop a new emerging chemoinformatic tool: read-across structure-property relationship (RASPR). The RASPR method can be applicable to both large and small datasets as it uses various similarity and error-based measures. It has also been observed that RASPR models tend to have an increased external predictivity compared to the corresponding QSPR models. In this study, we have modeled the power conversion efficiency (PCE) of organic dyes used in dye-sensitized solar cells (DSSCs) by using the quantitative RASPR (q-RASPR) method. We have used relatively larger classes of organic dyes-Phenothiazines (n=207), Porphyrins (n=281), and Triphenylamines (n=229) for the modelling purpose. We have divided each of the datasets into training and test sets in 3 different combinations, and with the training sets we have developed three different QSPR models with structural and physicochemical descriptors and validated them with the corresponding test sets. These corresponding modeled descriptors were used to calculate the RASPR descriptors using a Java-based tool RASAR Descriptor Calculator v2.0 (https://sites.google.com/jadavpuruniversity.in/dtc-lab-software/home), and then data fusion was performed by pooling the previously selected structural and physicochemical descriptors with the calculated RASPR descriptors. Further feature selection algorithm was employed to develop the final RASPR PLS models. Here, we also developed different machine learning (ML) models with the descriptors selected in the QSPR PLS and RASPR PLS models, and it was found that models with RASPR descriptors superseded in external predictivity the models with only structural and physicochemical descriptors: RMSEP reduced for phenothiazines from 1.16-1.25 to 1.07-1.18, for porphyrins from 1.60-1.79 to 1.45-1.53, for triphenylamines from 1.27-1.54 to 1.20-1.47.

Investigating the Effects of Fluorine Substituents on Organic Dyes in Dye-Sensitized Solar Cells

We synthesized and evaluated five organic dyes that featured both mono- and di-substituted fluorine atoms for application in dye-sensitized solar cells (DSSCs). The dye structure was designed with N, N-dimethylaniline as a donor, fluorophenyl as an π-conjugated bridge, and cyanoacetic acid as an anchoring and acceptor group. The fluorine substituents are strong electron-withdrawing groups, introducing different numbers and positions of fluorine atoms (ortho and meta) that were expected to the ability of the acceptor parts of the dye. The results showed that adding the fluorine mono-substitution in the ortho position can enhance the efficiency of the solar cells in comparison with the meta-substitution and unsubstituted one. However, the di-substitution by fluorine atoms in two ortho positions and ortho, meta positions reduced the performance of the solar cells. The reason was related to the effect of π-conjugation between the fluorine substituent and the carbonyl group of the carboxylic acid. The DSSCs based on dye 14 achieved the best results with power conversion efficiency (PCE) = 3.33%, (Jsc = 5.43 mA cm-2, Voc = 0.81V and FF = 75.85%) under standard conditions with I3-/I- as the electrolyte.

Natural dyes for dye-sensitized solar cells (DSSCs): An overview of extraction, characterization and performance

Dye-sensitized solar cells (DSSCs) have emerged as a promising technology for solar energy conversion due to their affordability and adaptability. Natural dyes derived from various botanical and fruit sources are gaining attention as an eco-friendly alternative to synthetic counterparts in DSSCs. This comprehensive review offers insights into the extraction techniques, characterization methods and effectiveness of natural dyes as sensitizers in DSSCs. Moreover, it examines the variables impacting the efficiency of DSSCs using natural dyes and investigates strategies to enhance their overall performance. By presenting this comprehensive overview, the paper aims to underscore the viability of natural dyes for DSSCs, promoting continued exploration and advancement in this area of research.

Screening novel candidates of ZL003-based organic dyes for dye-sensitized solar cells by modifying auxiliary electron acceptors: A theoretical study

In this work, a series of ZL003-based free-metal sensitizers with the donor-acceptor-π- conjugated spacer-acceptor (D-A-π-A) structure were designed by modifying auxiliary electron acceptors for the potential application in dye-sensitized solar cells. The energy levels of frontier molecular orbitals, absorption spectra, electronic transition, and photovoltaic parameters for all studied dyes were systematically evaluated using density functional theory (DFT)/time-dependent DFT calculations. Results illustrated that thienopyrazine (TPZ), selenadiazolopyridine (SDP), and thiadiazolopyridine (TDP) are excellent electron acceptors, and dye sensitizers functionalized by these acceptors have smaller HOMO-LUMO gaps, obviously red-shifted absorption bands and stronger light harvesting. The present study revealed that the photoelectric conversion efficiency (PCE) of ZL003 is around 13.42 % with a JSC of 20.21 mA·cm−2, VOC of 966 mV and FF of 0.688 under the AM 1.5G sun exposure, in good agreement with its experimental value (PCE = 13.6 ± 0.2 %, JSC = 20.73 ± 0.20 mA·cm−2, VOC = 956 ± 5 mV, and FF = 0.685 ± 0.005.). With the same procedure, the PCE values for M4, M6, and M7 were estimated to be as high as 19.93 %, 15.38 %, and 15.80 % respectively. Hence, these three dyes are expected to be highly efficient organic sensitizers applied in practical DSSCs.

Exploring the potential of natural dyes in DSSCs: Innovations for efficient light harvesting and charge separation through Co-sensitization

Dye-sensitized solar cells (DSSCs) are a cost-effective and environmentally benign third-generation photovoltaic technology that is gaining prominence in the changing renewable energy sector. Our study presents the concept of co-sensitization, which involves the combination of TiO2QD with MWCNT/TiO2, in order to improve the efficiency of solar energy conversion greatly. The efficiency of these solar cells is highly dependent on the efficacy of the dye as a photosensitizer. The results indicate that DSSCs employing the co-sensitized approach with TiO2QD achieved an efficiency (η) of 0.331, an open circuit voltage (Voc) of 0.539 (V), a short circuit current density (Jsc) of 0.095 (mA/cm2), and a fill factor (FF) of 37 %. On the other hand, DSSCs utilizing the MWCNT/TiO2 photoanode demonstrated an efficiency (η) of 0.213 %, an open circuit voltage (Voc) of 0.509 (V), a short circuit current density (Jsc) of 0.076 (mA/cm2), and a fill factor (FF) of 17 %. In the ever-changing world of renewable energy, cutting-edge methods like co-sensitization could boost solar energy conversion technology efficiency and sustainability. Innovative methods like employing plant leaf dye as photosensitizers for DSSCs are eco-friendly and could cut production costs. Using natural dyes supports sustainable practices and makes solar energy production more affordable and accessible.

Exploration of 4-substituted thiophene-based azo dyes for dye-sensitized solar cells and non-linear optical materials: synthesis and an in silico approach.

This work examines the effects of changing the secondary donors' donating strengths at the thiophene ring's fourth position in a range of dyes designated SR1 to SR9. The DFT results indicate that the molecular planarity is greatly affected by the placement of the secondary donor at position four, which changes the charge transfer (CT) characteristics in the thiophene-azo-salicylic acid backbone. These results are corroborated by TD-DFT analysis, which indicates that as the secondary donor's donating strength increases, so does the vertical absorption maximum. Based on the computed photovoltaic characteristics, these dyes perform better from SR1 to SR5. Research on dye@TiO2 clusters suggests a potential for binding with TiO2, which might cause the dye@TiO2 clusters' absorbance to shift red. Additionally, computed linear and non-linear optical (NLO) properties exhibit similar trends to those observed for DSSC performance. The experimental results, which include HOMO and LUMO energies as well as initial absorption in dimethylformamide (DMF), match very well with the patterns seen in DFT and TD-DFT calculations. The high thermal stability of SR1 to SR4 is indicated by thermogravimetric analysis (TGA), indicating their practical applicability in non-linear optics (NLO) and DSSC applications. The efficiencies of the produced DSSCs vary; SR4 has the highest efficiency (4.50 ± 0.1), and SR1 has the lowest (0.37 ± 0.1). The combined effects of theoretical and experimental DSSC results demonstrate the vital role of secondary donors in influencing molecular characteristics and NLO and DSSC performance.

Retraction Note: Performance of Natural Dyes in Dye-Sensitized Solar Cell as Photosensitizer

Retraction Note: Performance of Natural Dyes in Dye-Sensitized Solar Cell as Photosensitizer

Preparation and Performance of ZnO and ZnO/MnO<sub>2</sub> Nanostructures as Anode Electrodes in DSSCs

Nanoparticles and nanocomposites prepared by the hydrothermal method (ZnO, ZnO/MnO2) were used to build dye-sensitized solar cells (DSSCs), which were used as photoelectrodes using two natural dyes as the absorbent media: red (Hibiscus sabdariffa) and green (Apium graveolens). The results showed the efficiency of the green dye in DSSCs is superior to the red dye in terms of conversion efficiency (η). The purpose of the study is to improve the performance of dye solar cells. The properties of nanomaterials were studied by X-ray diffraction (XRD), scanning electron microscopy (FE-SEM), and transmission electron microscopy (TEM) for the analysis of ZnO NPs and ZnO/MnO2, whereas the sizes of the prepared materials are within the size of 1–100 nm. The solar cell parameters were obtained from simple (I-V) measurements for nanomaterials prepared using two-dye DSSCs where Isc represents the short circuit current through the solar cell when the voltage across the solar cell is zero, and Voc represents the open circuit voltage across the solar cell and is the maximum voltage available from the solar cell. The photoelectrochemical properties of the two dye DSSCs in this study were calculated at 22.53 mW/cm2 of the light intensity.

The performance of organic dyes in dye-sensitized solar cells: From theoretical calculation to experiment

Herein, two phenothiazine-based organic molecules PTZ-6 and PTZ-19 were designed and synthesized. Firstly, the molecular structures were optimized through density functional theory (DFT) using CAM-B3LYP method and 6-311G (d) group based on Gaussian09 program. And the UV–vis absorption spectrum of the dye molecules also being simulated with time dependent density functional theory (TD-DFT). Subsequently, we calculated the open circuit voltage (VOC), filling factor (FF) and other data of the devices with these two dyes, the simulated Power Conversion Efficiency (PCE) values are 5.9% and 7.2% for PTZ-6 and PTZ-19. In addition, to verify the reliability of our calculation method, these two dyes were synthesized, and a detailed analysis was conducted on the photophysical and electrochemical properties of two dye molecules, as well as their device performance. The PCE obtained from the experiment were 3.99% and 4.39%, respectively. The experimental data is close to the theoretical data, and the regularity of the performance differences between these two dyes has been well verified. Our research provides a relatively reliable theoretical calculation method for designing and predicting the performance of organic dyes for dye-sensitized solar cells (DSSCs).

Exploiting the role of coadsorbents on photovoltaic performances of dye sensitized solar cells: A DFT study

We examine the role of coadsorbents on dye-sensitized solar cells (DSSCs) with metal-containing and metal-free organic dyes to assess the performance computationally. The results corroborate well with the reported experimental results of Ru-containing dyes exhibiting that the co-adsorbent with longer alkyl chains anchored on the semiconductor surface lower the electron recombination process. The calculated results reveal that the co-adsorbents influence the conduction band energy level and that improve the effective density of states augmenting the forward electron transmission as well as reducing the electron recombination process. The role of co-adsorbents with metal-free organic dyes in DSSCs has also been examined. The computational results suggest that the metal-free organic dyes employed in DSSCs can achieve similar efficiency as reported with metal-organic sensitizers. The results revealed that co-adsorbents grafted through non-covalent interaction are more efficient in improving the efficiency of the DSSCs than co-adsorbents grafted through covalent bonds. The coadsorbents, 1-dimethoxyphosphoryloctadecane with long alkyl chains anchored on the semiconductor surface through hydrogen bonding interactions highly improve the effective density of states resulting in better forward electron transmission and may be one of the parameters to enhance the DSSCs efficiency.

Steric and Electronic Effect in Unsymmetrical Squaraine Dyes for Dye-Sensitized Solar Cells

Steric and Electronic Effect in Unsymmetrical Squaraine Dyes for Dye-Sensitized Solar Cells

Squaric Acid Core Substituted Unsymmetrical Squaraine Dyes for Dye-Sensitized Solar Cells: Effect of Electron Acceptors on Their Photovoltaic Performance

The design and development of sensitizing dyes possessing wide-wavelength photon harvesting encompassing visible to near-infrared (NIR) wavelength regions are unavoidable for increasing the overall efficiency of dye-sensitized solar cells (DSSCs). In this study, three far-red-sensitive squaraine sensitizers were designed computationally, synthesized, and characterized, aiming towards their suitability as a potential sensitizer for DSSCs. It has been found that the incorporation of an electron acceptor moiety in the central squaraine core brought about a red shift in the absorption maximum (λmax) and the emergence of a secondary absorption band in the blue region, thus broadening the photon-harvesting window. In addition, it also lowered the dye’s HOMO energy level enabling a facile regeneration of the photo-excited dye, which improved the photovoltaic performance of SQ-223, exhibiting a photoconversion efficiency (PCE) of 4.67%. Thereafter, to address the issue of wide-wavelength photon harvesting, DSSCs were fabricated by co-adsorbing two complementary dyes SQ-223 and D-131 in various molar ratios. The DSSC fabricated with D-131 and SQ-223 in 9:1 molar ratio displayed the best photovoltaic performance with a PCE of 5.81%, a significantly higher PCE when compared to corresponding individual dye-based DSSCs containing D-131 (3.94%) and SQ-223 (4.67%).

A Review of Advances on Natural Dye Sensitized Solar Cells (NDSSCs)

Currently, the situation of the economy is drastically affecting the growth and development of some growing nations with regard to the energy sector. Most developing countries still depend majorly on fossil fuels. Considering the environmental nuisance arising from the dangerous emissions from the combustion of fossil fuels and climate concerns, there is urgent need to seek other alternative energy sources to meet up with the global energy consumption demands as the human population is steadily on the increase. Energy from the sun is one of the most alternative sources that can be assessed freely as well as help in mitigating global climate change. Recent advances on dye sensitized solar cells (DSSC) using natural dyes is a welcome advancement for replacing high cost ruthenium dye. The application of natural dye for DSSC is due to their abundance in nature, low cost, simple and safe extraction from various natural resources without requiring complex synthetic procedures. Dye enhances the performance of a DSSC by providing the source of photo excited electrons. Recently, there has been research on areas that supports the exploration of different photoactive natural dyes. In this paper, we reviewed some natural dyes, energy conversion efficiencies of NDSSCs, methods of dye extraction, characterization and various fabrication techniques for improved DSSC performance from various researched articles. It was observed that there were variations in the recorded DSSCs performances and this can be attributed to steps employed by the researchers in the methods of dye extraction and DSSC fabrication.

A Green Approach to Natural Dyes in Dye-Sensitized Solar Cells.

Solar cells are pivotal in harnessing renewable energy for a greener and more sustainable energy landscape. Nonetheless, eco-friendly materials for solar cells have not been as extensive as conventional counterparts, highlighting a significant area for further investigation in advancing sustainable energy technologies. This study investigated natural dyes from cost-effective and environmentally friendly blueberries and mulberries. These dyes were utilized as alternative sensitizers for dye-sensitized solar cells (DSSCs). Alongside the natural dyes, a green approach was adopted for the DSSC design, encompassing TiO2 photoanodes, eco-friendly electrolytes, and green counter-electrodes created from graphite pencils and candle soot. Consequently, the best-optimized dye sensitizer was mulberry, with an output power of 13.79 µW and 0.122 µW for outdoor and indoor environments, respectively. This study underscored the feasibility of integrating DSSCs with sensitizers derived from readily available food ingredients, potentially expanding their applications in educational kits and technology development initiatives.