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For photoelectrochemical water splitting, tungsten trioxide (WO3) films with a monoclinic structure were synthesized on fluorine-doped tin oxide coated glass substrates with a vacuum evaporation method. To control the WO3 film thickness from 0.42 to 5.6 μm, the crystal orientation was intergraded from the (200) crystal plane to the (002) one. In x-ray diffraction measurements, the intensity ratio of the (002) crystal plane to the (200) one was defined as rp. In the WO3 photoelectrode with higher (002)-preferred orientation, the photocurrent continued to flow even when the incident light against the photoelectrode was completely blocked after the irradiation for 60 s. This suggests that hydrogen continues to be produced owing to the electrons charged by the formation of a hydrogen tungsten bronze (HxWO3) phase. After 72 s, the photocurrent density of the WO3 photoelectrode with rp = 42 became one-tenth of the value before the incident light was blocked. This charge release time was remarkably long compared to those of the WO3 photoelectrodes with (200)-preferred orientation and non-orientation. Therefore, it was considered that the hydrogen ion diffusion through the defects in the WO3 crystals tends to occur in the [002] crystal direction. However, the improvement in the (002)-preferred orientation can facilitate the structural change from the WO3 phase to the HxWO3 one for the entire film. [ABSTRACT FROM AUTHOR]

The main challenge for solar cell devices is harvesting photons beyond the visible by reaching the red-edge (650–780 nm). Dye-sensitized solar cell (DSSC) devices combine the optical absorption and the charge separation processes by the association of a sensitizer as a light-absorbing material (dye molecules, whose absorption can be tuned and designed) with a wide band gap nanostructured semiconductor. Conformational and environmental effects (i.e., solvent, pH) can drastically influence the photophysical properties of molecular dyes. This study proposes a combined experimental and computational approach for the comprehensive investigation of the electronic and vibrational properties of a unique class of organic dye compounds belonging to the family of red-absorbing dyes, known as squaraines. Our focus lies on elucidating the intricate interplay between the molecular structure, vibrational dynamics, and optical properties of squaraines using state-of-the-art density functional theory calculations and spectroscopic techniques. Through systematic vibrational and optical analyses, we show that (i) the main absorption peak in the visible range is influenced by the conformational and protonation equilibria, (ii) the solvent polarity tunes the position of the UV–vis absorption, and (iii) the vibrational spectroscopy techniques (infrared and Raman) can be used as informative tools to distinguish between different conformations and protonation states. This comprehensive understanding offers valuable insights into the design and optimization of squaraine-based DSSCs for enhanced solar energy conversion efficiency. [ABSTRACT FROM AUTHOR]

The New Journal of Chemistry, published by The Royal Society of Chemistry and the Centre National de la Recherche Scientifique, features a variety of research articles on topics such as nanocrystals synthesis, luminescence efficiency improvement, and visible light photocatalysis. The journal covers a wide range of subjects, including biochemistry, pharmacology, and environmental catalysis, providing valuable insights into cutting-edge research in the field of chemistry. With a focus on innovative directions in chemistry, the journal aims to connect the global chemistry community and reinvest profits back into the field. [Extracted from the article]

Vanadium-doped zinc oxide (V-doped ZnO) nanostructures synthesized using a solution combustion method are exploited as efficacious photoanode materials for N719 dye-sensitized solar cells. The effect of fuels, including polyethylene glycol (PEG-400) and urea, on the morphological and structural properties of vanadium-doped ZnO nanostructures is elucidated in detail. Using PEG-400 as fuel, the doping of vanadium on ZnO nanostructures effectively transformed the nanoparticles into nanorods, whilst the conversion of nanorods into nanoparticles was conducted with the aid of urea fuel. Optical measurements and X-ray diffraction showed no major shift in the wavelength and peak position, respectively, indicating that vanadium is present on the surface of ZnO rather than in the interstitial position. The high surface area of the material revealed that mesopores present in the photoanode materials, which was 129 m2 g−1 for the sample synthesized using PEG-400 as fuel, offered higher power conversion efficiency (PCE) due to higher pore volume (0.317 cm3 g−1) and dye adsorbing capability as revealed through BET analysis. The PCE of the PEG-400 fuel used sample showed 5.4% efficiency, whereas the urea fuel sample exhibited 4.9% efficiency. IPCE measurements displayed a wavelength maximum at 510 nm with 22.14% of the IPCE value, indicating that the PEG-400 fuel sample (ZnO–V5%) shows the highest efficiency among other DSSC devices. [ABSTRACT FROM AUTHOR]

The document is a contents list from the journal CrystEngComm, focusing on the design and understanding of solid-state and crystalline materials. It includes articles on topics such as zinc sulfide clusters, salt-inclusion compounds, crystal structure effects, and composite electrodes for organic pollutant degradation. The journal aims to connect the world with the chemical sciences and invest profits back into the chemistry community, published by The Royal Society of Chemistry. [Extracted from the article]

Developing high-performance electrolytes combining high efficiency and durability remains challenging for energy devices. Herein, lyotropic liquid crystal (LLC) electrolytes (Brij58-LLCn) were designed for quasi-solid-state dye-sensitized solar cells (DSSCs) based on commercially available polyethylene glycol-20-hexadecyl ether (Brij58) in combination with different weight contents (30%, 40%, and 50%) of a liquid electrolyte (LE). The liquid crystal behavior, molecular arrangement, electrochemical performance, and DSSC performance of Brij58-LLCn were investigated. Self-assembly of Brij58 and a LE formed a lamellar phase with a focal conic texture. The LE was concentrated to construct layered conducting channels and these channels were expanded by increasing the LE, which was beneficial for charge transfer. The best ionic conductivity of 9.01 mS cm−1 was achieved by Brij58-LLC50. DSSCs containing Brij58-LLCn exhibited promising photovoltaic performance and satisfactory thermal stability. The introduction of commercial Brij58 has extended the path of constructing 'liquid' channels in lyotropic liquid crystals for enhancing the performance of energy devices, which provides new ideas for the development of electrolytes in advanced energy devices. [ABSTRACT FROM AUTHOR]

In time-of-flight secondary ion mass spectrometry (ToF-SIMS), multivariate analysis (MVA) methods such as principal component analysis (PCA) are routinely employed to differentiate spectra. However, additional insights can often be gained by comparing processes, where each process is characterized by its own start and end spectra, such as when identical samples undergo slightly different treatments or when slightly different samples receive the same treatment. This study proposes a strategy to compare such processes by decomposing the loading vectors associated with them, which highlights differences in the relative behavior of the peaks. This strategy identifies key information beyond what is captured by the loading vectors or the end spectra alone. While PCA is widely used, partial least-squares discriminant analysis (PLS-DA) serves as a supervised alternative and is the preferred method for deriving process-related loading vectors when classes are narrowly separated. The effectiveness of the decomposition strategy is demonstrated using artificial spectra and applied to a ToF-SIMS materials science case study on the photodegradation of N719 dye, a common dye in photovoltaics, on a mesoporous TiO2 anode. The study revealed that the photodegradation process varies over time, and the resulting fragments have been identified accordingly. The proposed methodology, applicable to both labeled (supervised) and unlabeled (unsupervised) spectral data, can be seamlessly integrated into most modern mass spectrometry data analysis workflows to automatically generate a list of peaks whose relative behavior varies between two processes, and is particularly effective in identifying subtle differences between highly similar physicochemical processes. [ABSTRACT FROM AUTHOR]

The enormous amount of solar power and its state-of-the-art capturing technology that produces electricity, increases the grid interconnection rate of photovoltaic (PV) plants. Prior knowledge of the aperiodic characteristics of solar energy received by the Earth's surface is essential for PV plants to ensure reliable operation and stable, secure grid connections. Power generation under diffused sunlight by PV plants with the most widely used first-generation solar cells has significant limitations. A dye-sensitized solar plant (DSSP), utilizes dye-sensitized solar cell (DSSC) technology, remains active in low light conditions. Though the activeness enables such plants to generate electricity throughout the year while receiving diffuse sunlight, unlike conventional solar technologies the plants have a requirement of knowledge of future power generation. This could be the first paper to report on the generated power forecast for such plants. The study has utilized a machine learning approach with a proposed DSSP model for the forecast. Spyder, an open-source integrated development environment, is the test workbench for the experimentation. The results show the robustness and reliability of the method, regardless of the weather conditions in the test area. The DSSP, along with the prediction model, will moderately overcome the shortcomings of power generation under diffuse daylight with intermittent solar radiation and grid connections. [ABSTRACT FROM AUTHOR]

To examine the relationship between chemical structure modification and photovoltaic performance, we designed six metal-free organic molecules (M2-M7) of structure D-π1-A-π2-A based on the base molecule M1 of structure D-π1-π2-A, introducing a new auxiliary acceptor (A) and varying the π2-spacer at the same time, to study their performance in dye-sensitized solar cells. Using density functional theory (DFT) and time-dependent DFT (TD-DFT) methods, several parameters were calculated and discussed, including LUMO and HOMO energy levels of the HOMO–LUMO energy gap, frontier molecular orbitals, absorption properties, nonlinear optical properties (NLO), light-harvesting efficiency (LHE), electron injection driving force (ΔGinj), dye regeneration driving force (ΔGreg), reorganization energy (λtotal), and vertical dipole moment (μnormal) of the studied dyes (M1–M7). The results of the proposed dyes proved promising for use as sensitizers in the DSSC device due to their lower energy gap, red- and NIR-shifted absorption band, higher LHE and NLO properties, lower ΔGreg and λtotal values, negative ΔGinj value, and higher μnormal value reflecting higher VOC compared to the reference dye M1. The results of these proposed dyes (M2-M7) will be considered favorable indicators for experimenters to synthesize effective dyes for use in the DSSC device. [ABSTRACT FROM AUTHOR]

The phenothiazine-derivative dyes have been designed using phenothiazine group (donor part), thienothiophene (spacer part), and different acid groups (electron-acceptor part). Time-dependent density functional theory (TD-DFT) and density functional theory (DFT) have been used to study the electronic and optical properties of the designed dyes (B1–B10). The dye B8 has planar conformations with a dihedral angle of 0.15° which indicates electron delocalization over the molecules. The dye B6 has a low chemical hardness value. The energy gap, ionization potential, electron affinity, and chemical hardness of the dyes have been computed, and efficiency has been analyzed. The B8 dye sensitizer has a higher dipole moment (5.324 Debye) compared to the other sensitizers, due to the presence of two cyano groups in the acceptor parts. The NLO characteristics have been determined based on the polarizability and first-order hyperpolarizability values of the designed dyes. The LHE values of dye molecules ranged from 0.75 to 0.89 eV. The dye sensitizers B6 and B8 have high efficient values compared with other designed dyes. [ABSTRACT FROM AUTHOR]

[Display omitted] • CuSe-Co 3 Se 4 @VSe 2 nanotube clusters were synthesized by a facile template method. • CuSe-Co 3 Se 4 @VSe 2 was used as a bifunctional catalyst for HER and DSSCs. • CuSe-Co 3 Se 4 @VSe 2 had lower overpotential for basic HER (76 mV@10 mA cm−2). • The PCE (9.64%) of CuSe-Co 3 Se 4 @VSe 2 was much higher than that of Pt (8.39%). Among the various non-precious metal catalysts that drive hydrogen evolution reactions (HERs) and dye-sensitized solar cells (DSSCs), transition metal selenides (TMSs) stand out due to their unique electronic properties and tunable morphology. Herein, the multicomponent selenide CuSe-Co 3 Se 4 @VSe 2 was successfully synthesized by doping with metal element vanadium and selenization on the copper-cobalt carbonate hydroxide (CuCo-CH) template. CuSe-Co 3 Se 4 @VSe 2 exhibited the dandelion-like cluster structure composed of hollow nanotubes doped with VSe 2 nanoparticles. Due to the unique structure and the synergistic effect of various elements, CuSe-Co 3 Se 4 @VSe 2 showed excellent alkaline HER and DSSC performances. The DSSC based on CuSe-Co 3 Se 4 @VSe 2 exhibited an impressive power conversion efficiency (PCE) of 9.64 %, which was much higher than that of Pt (8.39 %). Besides, it possessed a low HER overpotential of 76 mV@10 mA cm−2 and a small Tafel slope of 88.9 mV dec−1 in 1.0 M KOH. [ABSTRACT FROM AUTHOR]

Owing to the high cost of installation and operation, distributed flexible AC transmission system (FACTS) technology gives opportunity to provide costeffective solution in power system operation and control. A distributed static series compensator (DSSC) is a series FACTS device and it is placed equidistantly placed on the existing line to vary the line current. Active power can be controlled in the line with the help of DSSC. This paper presents DSSC for active power flow control to enhance system loadability index and to minimize reactive power generation by generators. Since DSSC is of low power. a small value of reactance is emulated in the line. Large number of DSSC's are distributed along the transmission line at regular intervals to realize considerable change in the current. A particle swarm optimization is implemented to determine DSSC's emulated reactance optimally. In this condition, all the lines flowing power in their limits with increased loading condition. Maximum system loadability index is evaluated by employing optimal number of DSSC's on the line. A multiobjective problem is formulated. One objective function is formed such that no line would become overloaded even when loading is increased. Other objective is formulated to minimize reactive power generation by generators. A compromise solution is investigated for optimally connected of DSSC devices to achieve both the objective functions. IEEE 14 bus system is taken for MATLAB simulation of DSSC compensated system. [ABSTRACT FROM AUTHOR]

Dye-sensitized solar cells (DSSCs) are composed of a semiconductor oxide, a photosensitive dye, an electrolyte, and a counter electrode, in which platinum is generally used. In order to reduce production costs, alternative materials such as graphite can be used as a counter electrode. The aim of this work was to develop a counter electrode for a DSSC using graphite extracted from exhausted dry batteries. TiO2 was used as the system anode, with natural dye extracted from Beta vulgaris var. esculenta (beetroot) and an electrolyte containing a redox pair of I3−/3I−. The graphite used as counter electrodes was extracted from three different dry batteries. The cells were assembled in sandwich format with an active area of 0.2 cm2. The characterization techniques used included UV–visible spectroscopy, scanning electron microscopy, x-ray fluorescence, open-circuit potential photo-chronoamperometry curves, and electrochemical impedance spectroscopy measurement. The results showed that the counter electrodes had an undefined morphology and contained small amounts of metals Mn, Fe, Ni, Zn, Pb, Ti, and Zr. The electrochemical measurements showed that the devices were photosensitive and that among the counter electrodes applied, the one that showed the most significant results in terms of photoconversion efficiency (PCE) was produced with graphite extracted from Sample 2, with J (mA cm−2) = 0.078 ± 0.010 and PCE = 0.016 ± 0.001%. Sample 2, using cellulose acetate (CLA) to provide better uniformity of counter electrodes, improved the dye solar efficiency, with current density (J) of 0.16 mA cm−2 ± 0.02. [ABSTRACT FROM AUTHOR]

We investigate theoretically the design and application of nine triazine (Tr)-core star-shaped molecules built with thiophene (Th), phenyl (Ph), and carbazole (Cz) moieties in dye-sensitized solar cells (DSSCs) and bulk heterojunction (BHJ) organic solar cells. Density functional theory and time-dependent density functional theory are employed to rationalize the electronic structure, charge transfer properties, and photovoltaic performance of these systems. Tr-Th-Cz and Tr-Ph-p-Th-Cz display power conversion efficiency (PCE ) values close to 30% due to a favorable alignment of the energy levels. Computed open-circuit voltage values show that lack of π-bridges, as in the Tr-Th and Tr-Cz, favor higher voltage generation. Systems containing thiophene (Th) and carbazole (Cz) present the most favorable values for efficient electron injection and dye regeneration. Furthermore, the incorporation of these Th and Cz donor substituents into the triazine core combined with π-bridges significantly impacts other optoelectronic properties of the organic solar cells. The computed high singlet–triplet gap values indicate limited potential of these molecules as thermally activated delayed fluorescence (TADF) emitters for applications in organic light-emitting diodes (OLEDs). [ABSTRACT FROM AUTHOR]

Accurately predicting the power conversion efficiency (PCE) in dye‐sensitized solar cells (DSSCs) represents a crucial challenge, one that is pivotal for the high throughput rational design and screening of promising dye sensitizers. This study presents precise, predictive, and interpretable machine learning (ML) models specifically designed for Zn‐porphyrin‐sensitized solar cells. The model leverages theoretically computable, effective, and reusable molecular descriptors (MDs) to address this challenge. The models achieve excellent performance on a "blind test" of 17 newly designed cells, with a mean absolute error (MAE) of 1.02%. Notably, 10 dyes are predicted within a 1% error margin. These results validate the ML models and their importance in exploring uncharted chemical spaces of Zn‐porphyrins. SHAP analysis identifies crucial MDs that align well with experimental observations, providing valuable chemical guidelines for the rational design of dyes in DSSCs. These predictive ML models enable efficient in silico screening, significantly reducing analysis time for photovoltaic cells. Promising Zn‐porphyrin‐based dyes with exceptional PCE are identified, facilitating high‐throughput virtual screening. The prediction tool is publicly accessible at https://ai‐meta.chem.ncu.edu.tw/dsc‐meta. [ABSTRACT FROM AUTHOR]

Developing electrode materials with improved catalytic activity is inevitable (i) to achieve efficient electro-catalytic water splitting (EWS) and (ii) to construct high performance dye sensitized solar cells (DSSCs). To this aim, Nitrogen (N)-doped carbon-wrapped bimetallic CoCu alloys (i.e, CN@CoCu) are prepared by directly annealing the Cu-loaded Zeolitic Imidazolate Framework-67 (ZIF-67) metal-organic framework (MOF) and employed as (i) working electrode in EWS and (ii) counter electrode (CE) in DSSCs. The ZIF-67 MOF acts as a self-sacrificing template for the formation of CN@CoCu electrodes, whose electro-catalytic activity can be optimized by tuning the Co/Cu molar ratio (Cu = 0, 5%, 10%, 15% and 20%). The addition of 15% of Cu into the ZIF-67 (i.e., CN@CoCu-15), as the working electrode in water splitting has achieved lowest overpotential values of 91 and 256 mV towards hydrogen evolution reaction and oxygen evolution reaction, respectively. Also, for DSSCs applications, the same CN@CoCu-15 sample as CE displays an improved catalytic activity by 21% higher than that of conventional Pt CE towards tri-iodide redox reaction. Consequently, the CN@CoCu-15 based DSSCs device has achieved a PCE of 7.10% which is larger than that of conventional platinum CE (6.69%). The mechanism behind the improved catalytic activity is attributed to the significant reduction in the work function of CN@CoCu-15 (4.82 eV) compared to CN@Co (5.2 eV), as evidenced from Kelvin Probe Force Microscopic analysis. These findings proposed an efficient bifunctional electro-catalytic material with improved water-splitting performance and solar energy conversion. [Display omitted] • Carbon-wrapped CoCu electrode is prepared for water splitting and DSSC application. • The work function of the electrocatalyst is minimum (4.87) when Co/Cu ratio is 15. • It displays excellent catalytic activity towards KOH and triiodide electrolyte. • Water splitting has been achieved at 1.53 V with prepared CN@CoCu-15. • In DSSC, a PCE of 7.10 % is achieved with prepared CN@CoCu-15 as counter electrode. [ABSTRACT FROM AUTHOR]

In the present mini-review article, we have compiled the previously reported literature on the fabrication of MXenes and their hybrid composite materials based electrochemical sensors for the determination of phenolic compounds and counter electrodes for platinum (Pt)-free dye-sensitized solar cells (DSSCs). MXenes are two-dimensional (2D) materials with excellent optoelectronic and physicochemical properties. MXenes and their composite materials have been extensively used in the construction of electrochemical sensors and solar cell applications. In this paper, we have reviewed and compiled the progress in the construction of phenolic sensors based on MXenes and their composite materials. In addition, co1.unter electrodes based on MXenes and their composites have been reviewed for the development of Pt-free DSSCs. We believe that the present review article will be beneficial for the researchers working towards the development of phenolic sensors and DSSCs using MXenes and their composites as electrode materials. [ABSTRACT FROM AUTHOR]

Perovskite solar cells (PSCs) have been on the forefront of advanced research for over a decade, achieving constantly increasing power conversion efficiencies (PCEs), while their route towards commercialization is currently under intensive progress. Towards this target, there has been a turn to PSCs that employ a carbon electrode (C-PSCs) for the elimination of metal back contacts, which increase the cost of corresponding devices while at the same time have a severe impact on their stability. Chalcogenides are chemical compounds that contain at least one chalcogen element, typically sulfur (S), selenium (Se), or tellurium (Te), combined with one metallic element. They possess semiconducting properties and have been proven to have beneficial effects when incorporated in a variety of solar cell types, including dye sensitized solar cells (DSSCs), quantum dot sensitized solar cells (QDSSCs), and Organic Solar Cells (OSCs), either as interlayers or added in the active layers. Currently, an increasing number of studies have highlighted their potential for achieving high-performing and stable PSCs. In this review, the most promising results of the latest studies regarding the implementation of chalcogenides in PSCs with a carbon electrode are presented and discussed, merging two research trends that are currently on the spotlight of solar cell technology. [ABSTRACT FROM AUTHOR]

Fabricating photoanodes with a strong light-scattering effect can improve the photoconversion efficiency of dye-sensitized solar cells (DSSCs). In this work, a facile microwave hydrothermal process was developed to prepare Au@TiO2 core–shell nanostructures, and then the Au core was removed by etching, resulting in hollow TiO2. Morphological characterizations such as field emission scanning and transmission electron microscopy measurements have been used for the successful formation of core–shell and hollow TiO2 nanostructures. Next, we attempted to deposit the different-sized hollow TiO2-based microspheres simultaneously on the surface of small-sized TiO2 nanoparticles-based compact film as light-scattering layers via electrophoretic deposition. The deposited hollow TiO2 microspheres constitute bi- and tri-layers that not only improve the light-harvesting properties but also speed up the photogenerated charge transfer. Compared to commercial TiO2 compact film (4.75%), the resulting bi-layer and tri-layered films-based DSSCs displayed power conversion efficiencies of 6.33% and 8.08%, respectively. It is revealed that the deposited bi- and tri-layered films can enhance the light absorption ability via multiple photon reflection. This work validates a novel and controllable strategy to develop light-scattering layers with increased light-harvesting properties for highly efficient dye-sensitized solar cells. [ABSTRACT FROM AUTHOR]

Dye-sensitized solar cells (DSSCs) are among the most widely studied thin-film solar cells because of their cost-effectiveness, low toxicity, and simple fabrication method. However, there is still much scope for replacing current DSSC materials due to their high cost, low volume, and lack of long-term stability. Accordingly, indium tin oxide (ITO)-nanorod films were fabricated by electron (E)-beam evaporation using the glancing angle deposition method in this study. Then, the ITO-nanorod was treated with oxygen plasma via a bias-magnetron radio-frequency (RF) sputtering process to improve the efficiency of DSSCs under a varying gas flow rate of 20, 40, 60, 80, and 100 sccm. The field emission scanning electron microscopy (FE-SEM) investigation of the ITO film structure revealed that the obtained nanorod structures have slightly different diameters. At the same time, an increase in the oxygen flow rate resulted in a rougher film surface structure. In this, the lower sheet resistance was received because of rougher morphology. When comparing the DSSCs efficiency (η) test results, we found that at a gas flow rate of 100 sccm, the highest efficiency value showed 9.5%. On the other hand, the ITO-nanorod without plasma treatment exhibited the lowest η. Hence, plasma technology can be practically applied to improve the η of DSSC devices. This study will be a prototype of a highly advanced solar cell manufacturing method for the solar cell industry. [ABSTRACT FROM AUTHOR]

Integrating energy storage and harvesting devices have been major challenges and significant needs of the time for upcoming energy applications. Photosupercapacitors are combined solar cell-supercapacitor devices which can provide next-generation portable powerpacks. Owing to advantages like economic and environmental friendliness, dye-sensitized solar cells (DSSCs) offer vast potential for being integrated with energy accumulation devices like supercapacitors. Over the past few years, various types of harvesting cum storage power devices combining DSSCs and supercapacitors have been reported. Over time the devices have improved in both performance and stability providing a broad outlook to possible future advancements including commercialization. We still have many challenges that are yet to be resolved in order to take these powerpacks to the next level of applications in portable and wearable electronics and communication devices. In this context, a detailed analysis and comparison of already reported photo-powered integrated supercapacitors based on DSSCs would give further insights into future advancements. In this review, we have discussed the development of photosupercapacitors, their fabrication strategies, and different materials used as counter electrodes, electrolytes, and dye sensitizers. [ABSTRACT FROM AUTHOR]

An asymmetric zinc phthalocyanine dye (ZnPcT3C), bearing three tetraethylene glycol donor groups and one carboxylic acid anchoring group, was synthesized as a photosensitizer dye for dye‐sensitized solar cells (DSSCs). The tetraethylene glycol (TEG), consisting of four ethoxy units, works as an amphiphilic long‐chain donor group that greatly helped in reducing the molecular aggregation. Carboxylic acid group, on the other hand, an acceptor, together with TEG in ZnPcT3C functions as a 'push–pullʼ system suitable for DSSCs. Absorption spectra of ZnPcT3C in DMSO showed a strong sharp Q band in the infrared region 600–700 nm with (λmax = 682 nm) and a less intense soret band appeared in the region 300–400 nm with λmax = 340 nm. The zinc phthalocyanine (ZnPcT3C) exhibited molar extinction coefficient (ε) of 72,727 L mol−1cm−1. The emission was observed at λem = 695 nm upon excitation at 650 nm and exhibited a fluorescence decay of 2.82 ns. The ZnPcT3C dye sensitised solar cell (c = 1 mM) exhibited the power conversion efficiency (η) of 3.52% in chloroform in I−/I3 electrolyte under simulated 100% brightness. Cosensitization of ZnPcT3C with another auxiliary dye D131 in 1:1 ratio in a cocktail‐type DSSC attained the power conversion efficiency of twice as high as η = 6.27% in an identical condition. A mixture of D131 (λmax = 470 nm) dye with the ZnPcT3C phthalocyanine harvests sunlight across the visible spectra, enabling DSSCs to attain a large photocurrent and photovoltage, enhancing power conversion efficiency. [ABSTRACT FROM AUTHOR]

To achieve dye-sensitized solar cells (DSSCs) with high transparency, multi-color capability, and long-term durability for future applications across various fields, this study selected phenylthiophene with UV-absorbing properties as the dye electron donor, cyanoacetic acid as the electron acceptor, and a colorless biphenyl dye (6OBA) as the co-sensitizer. The effects of different alkyl chain lengths, densities, branching positions, and co-sensitization on the photovoltaic (PV) performance of the devices are investigated. In addition, the effect of dye molecules adsorbed on TiO2 films of different thicknesses on the optical transmittance of the devices was also analyzed. The results show that the developed dyes exhibit UV-selective absorption properties. The power conversion efficiencies (PCEs) of the semi-transparent DSSCs ranged from 0.51% to 0.89% under one sun illumination (100 mW cm−2) and from 3.78% to 5.94% under UVA LED illumination (365 nm, 150 μW cm−2). The corresponding visible light transmittance varied between 33.47% and 63.71%. At the same time, the DSSCs demonstrated long-term PCE stability after soaking for 1000 hours of full light irradiation. [ABSTRACT FROM AUTHOR]

TiO2 is one of the most studied semiconductor materials for the photoelectrochemical water splitting to hydrogen production, but it only responds to ultraviolet light. The introduction of organic compound is one of the common means to expand the visible light response of TiO2. In this work, rutile TiO2 nanowire arrays (NWs) were grown on conductive glass by a modified solvothermal method using oleic acid as the key additive. The obtained TiO2 NWs are characterized using x-ray diffraction, x-ray photoelectron spectroscopy, infrared spectroscopy and electrochemical characterization. The results show that the carboxyl groups arising from oleic acid are chemically bonded with the TiO2 NWs in the form of chelating bidentate, which increases the visible light absorption range and active sites of TiO2, and reduces the transfer resistance between the photoelectrode and the electrolyte. The photocurrent density is doubled to 0.17 mA cm−2 at 1.23 V vs. RHE. This work provides a novel idea for the design of metal oxide semiconductor photoanodes by adsorbing organic compounds. [ABSTRACT FROM AUTHOR]

The quest to enhance solar cell performance has long been driven by increasing energy demands and environmental concerns, and much progress has been achieved by way of interface modifications. As the demand for sustainable energy increases and environmental awareness pushes us toward cleaner solutions, the spotlight turns to stable and eco-friendly metal oxide semiconductors for photovoltaic applications. This research highlights the exceptional electronic and optical characteristics of ZrO2@GO nanoparticles, focusing on molecular electrostatic potential (MEP), nonlinear optical properties (NLO), and electron localization function (ELF). Our findings highlight that ZrO2@GO exhibits superior electronic characteristics compared to bare graphene oxide. This superiority motivates us for the co-sensitization of ZrO2@GO with squaraine dyes, which are well known for their strong light harvesting in dye-sensitized solar cells (DSSC). Using density functional theory (DFT) with Gaussian 09, we examine critical parameters that include the highest occupied molecular orbital (HOMO), lowest unoccupied molecular orbital (LUMO), energy gap, maximum wavelength (λmax), electron injection efficiency (ΔGinject), open-circuit voltage (Voc), reorganization energy (λreorg), among others. Our research highlights the high optical transmittance of ZrO2@GO, positioning it as a promising material for advanced optical, electrical, and light-harvesting devices with improved performance and efficiency. [ABSTRACT FROM AUTHOR]

This scientific paper presents a novel approach to explore and predict the potential of imidazole-based organic dyes for use in Dye-Sensitized Solar Cells (DSSCs) using a machine learning web application. The design of efficient and cost-effective organic dyes is critical to enhance the performance of DSSCs. Traditional experimental methods are time-consuming and resource-intensive, making it challenging to screen a large number of potential dyes. In this study, we propose a machine learning-based approach to accelerate the discovery process by predicting the photovoltaic performance of imidazole-based organic dyes. Machin learning predictions provide valuable insights into the expected PCE% and behaviors of the molecules toward DSSCs. Based on the RDKit library, several fingerprints such as Molecular ACCess System, Avalon, Daylight, Pharmacophore and Morgan with different radius (r2, r3, r4), were studied. In addition, more than 20 ML algorithms using different cross validation (3, 5, 7, 10) were also evaluated. Among of these, Deep Neural Network models of MLPRegressor algorithm based on the daylight fingerprint shows a significant coefficient of determination combined with the lowest errors. Utilize the trained ML models to screen of 50 million SMILE structure for identify promising imidazole and nitrogen-containing derivative as a doner group. By replacing the donor groups in the well-known MK2 dye structure with the top imidazole derivatives proposed by machine learning, significant improvements in PCE were observed, increasing from 7.70% to as high as 11.49%, representing nearly a 50% enhancement over the control. DFT calculations confirm the ML predictions and clarify the significantly higher oscillator strength and charge transfer properties of MK2-DM1, compared to MK2. This result provides a promising pathway for developing new dye materials that can push the efficiency limits of DSSCs, leading to more efficient solar energy conversion technologies in the future. In addition, a developed web application offers a user-friendly interface for researchers to input their molecular structures and obtain PCE% predictions toward DSSCs. This information can guide researchers in designing a new imidazole dye with high photovoltaic performance to validate and refine the predictions without time consuming. [ABSTRACT FROM AUTHOR]

A DFT/TD-DFT method was employed to study the effects of structural modification and solvent variation on the solubility, adsorptive, and photovoltaic properties of six porphyrins (A–F) obtained by structurally modifying two literature porphyrins A and D. The properties of interest were studied in vacuum, acetonitrile (AcCN), dichloromethane (DCM), dimethyl sulphoxide (DMSO), and ethanol (EtOH) for possible application of the molecules as sensitizers in dye-sensitized solar cells (DSSCs). Electronic absorption properties of the molecules were computed via potential energy surface scan, and thermodynamic data were obtained by DFT calculations in the selected media. Solubility properties of the molecules were mostly enhanced with DMSO as the solvent. The adsorptivity of the molecules onto mesoporous titanium (IV) oxide surface were predicted to be enhanced in the presence of DMSO. Most of the molecules were found to exhibit their highest photovoltaic activity measured in terms of the incident photon conversion efficiency (IPCE) in AcCN and DCM, rather than in DMSO due to its high viscosity and the ability to use its oxygen to form the catenating O-Ti4+ bond with the Ti4+ of the TiO2, causing inhibition of electron movement on the semiconductor surface. In general, the computed photovoltaic (PV) properties were found to be enhanced with -CO2H group as the substituent, and in AcCN or DCM as the solvent. [ABSTRACT FROM AUTHOR]

Perovskite-based DSSCs were manufactured using Sodium bismuth titanate (NBT) as a photoanode and their performance was extended studied by doping NBT perovskite with iron. The hydrothermal method was used to prepare pure NBT, and iron-doped NBT perovskite, which was deposited by spin coating on titanium oxide films previously prepared by screen printing. Pure and iron-doped NBT films were studied structurally, morphologically, and optically using X-ray diffraction, Field emission scanning electron microscope, photoluminescence spectra, and Fourier transform infrared. FESEM images showed some nanosheets appeared between agglomerated particles at the 8% Fe-doped NBT. The lead-free perovskite dye sensitized solar cell (DSSC) based on pure NBT showed highest conversion efficiency of 6.041%, highest external quantum efficiency, highest electron lifetime (2.17 s) and lowest ideality factor (3.52) compared to those DSSCs in which iron-doped NBT was used. This study proposes a nanoscale lead-free inorganic perovskite material that has been used in photovoltaic applications, and whose efficiency could be improved through future research.The current study was expanded to include studying the effects of photoresponse, response time and recovery timeof DSSCs based on Na0.5Bi0.5FexTi1−xO3. [ABSTRACT FROM AUTHOR]

Carbazole-based molecules play a significant role in dye-sensitized solar cells (DSSCs) due to their advantageous properties. Carbazole derivatives are known for their thermal stability, high hole-transport capability, electron-rich (p-type) characteristics, elevated photoconductivity, excellent chemical stability, and commercial availability. This review focuses on DSSCs, including their structures, working principles, device characterization, and the photovoltaic performance of carbazole-based derivatives. Specifically, it covers compounds such as 2,7-carbazole and indolo[3,2-b]carbazole, which are combined with various acceptors like benzothiadiazole, thiazolothiazole, diketopyrrolopyrrole, and quinoxaline, as reported over the past decade. The review will also outline the relationship between molecular structure and power-conversion efficiencies. Its goal is to summarize recent research and advancements in carbazole-based dyes featuring a D-π-A architecture for DSSCs. Additionally, this review addresses the evolution of carbazole-based hole-transport materials (HTMs), which present a promising alternative to the costly spiro-OMeTAD. We explore the development of novel HTMs that leverage the unique properties of carbazole derivatives to enhance charge transport, stability, and overall device performance. By examining recent innovations and emerging trends in carbazole-based HTMs, we provide insights into their potential to reduce costs and improve the efficiency of DSSCs. [ABSTRACT FROM AUTHOR]

The article discusses the synthesis of new indeno[1,2-b]pyrroles and pyrrole-fused isocoumarins in aqueous media using a three-component domino reaction. These compounds have shown various biological activities, including antimicrobial properties. The study explores the feasibility of preparing these compounds, which are structurally similar to known antimicrobial agents, and evaluates their antibacterial activity against different strains. The results show promising antimicrobial activities, suggesting the potential of these compounds as novel antimicrobial agents. [Extracted from the article]

In recent years, there is a growing interest in the development of sustainable sensitizers for the dye-sensitized solar cell (DSSC) applications. The earth-abundant transition metal complexes offer a potential alternative option to the problematic ruthenium-based dyes, owing to their interesting photophysical properties and eco-friendly nature. This review accounts in detail the development of sustainable late transition metal-sensitizers in the DSSCs. Attempts are made to comprehensively describe the various strategies involved in the molecular design of the potential dye-molecules as well as the methodologies involved in the cell-fabrication. We hope that this review will serve as a promptuary to the researchers and inspire further developments in this field. [ABSTRACT FROM AUTHOR]

Herein, we reported the synthesis of MnO2/ZIF-8 composite by employing two-step synthetic procedure. The synthesized samples have been characterized by utilizing various sophisticated physicochemical technique such as X-ray diffraction (XRD), scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS), and energy-dispersive X-ray (EDX) spectroscopy. The synthesized MnO2/ZIF-8 has been used as counter electrode (CE) for the fabrication of dye-sensitized solar cells (DSSCs). The effect of annealing temperature was studied, and the highest efficiency of 7.2% with a decent open-circuit voltage (Voc) of 0.77 V was achieved at 200 °C. The obtained efficiency of 7.2% is reasonable in comparison to the platinum (Pt)-based DSSCs (7.4%). This work proposed the construction of Pt-free CE for the development of cost-effective DSSCs with reasonable performance in terms of efficiency. [ABSTRACT FROM AUTHOR]

Dye-sensitized solar cells (DSSCs) exhibit considerable potential as a promising technology, particularly when addressing the challenge of replacing the costly Platinum (Pt) counter electrode (CE) with economically viable and chemically stable CE materials. This study examines the use of two-dimensional hexagonal-shaped nickel oxide nanosheets substituted with varying mol% of lithium (1, 3, and 5 %) (Li (1–5%)-NiO NSs) as the counter electrodes (CEs) for DSSCs. The facile hydrothermal method was employed for the preparation of NiO and Li (1–5 mol%)-NiO samples. The BET analysis of NiO and Li (1–5%)-NiO indicates that higher concentrations of Li1+ ions in Ni2+ ions sites lead to an increase in the overall surface area of NiO. This leads to an elevated number of exposed electrocatalytic active sites which resulted in enhancing the rate of reduction of I 3 − ions. The cyclic voltammetry (CV) result of 5 mol% of Li substituted NiO (5-LNO) shows outstanding electrocatalytic activity towards the redox reaction of I 3 − / I − redox mediator among the as-prepared CEs. The DSSCs assembled with 5-LNO CE show an excellent power conversion efficiency (η) of 5.84 % with short-circuit current (J s c) of 18.76 mAcm−2, and open-circuit voltage (V o c) of 0.80 V which is higher than Pt-based CE (η of 4.05 % with J s c of 10.16 mAcm−2, and V o c of 0.69 V). The DSSCs fabricated with 5-LNO CE exhibit excellent photovoltaic performance because of their high active surface area and enhanced electrical conductivity. The 5-LNO CE has low cost, significant electrocatalytic activity, less toxicity, and superior device efficiency than NiO, other Li (1–3%)-NiO, and Pt CEs, making it a suitable candidate for Pt-free DSSCs application. [ABSTRACT FROM AUTHOR]

The performance of dye-sensitized solar cells (DSSC) primarily depends upon many factors, such as the thickness of the semiconductor layer at the working electrode, dye/sensitizer concentration, and electrolyte. A methodical study is required in one place to deliberate the impact of all these factors on DSSC performance for better understanding and further advancement of the technology. This work emphasizes optimizing the absorption layer, specifically investigating the relationship between the thickness of the TiO2 layer and the concentration of N719 dye. The objective is to elucidate the interconnected effects of these parameters on the overall performance of the device. Additionally, the optimization of electrolyte composition was done with varying concentrations of additives, such as iodine, 4-tert-butyl-pyridine (TBP), guanidinium thiocyanate (GuNCS), and 1-butyl-3-methylimidazolium iodide (BMII) of electrolyte. Initially, the devices with varying TiO2 absorption layers were fabricated. The efficiency, fill factor (FF), open-circuit voltage (VOC), and short-circuit current (ISC) of devices were studied. The drop in open-circuit voltage (VOC) was noticed with the increase in thickness of the TiO2 layer. The highest efficiency was observed at 7.17% with the device fabricated using 6 absorption layer (17.46 μm) of TiO2, 0.7 mM concentration of N719 dye, and 0.03-M iodine, 0.1-M GuNCS, 0.5-M TBP, and 0.6-M BMII in electrolyte. Future developments in this research could focus on further fine-tuning these parameters for improved efficiency and exploring additional innovations in DSSC technology, ultimately contributing to the advancement of sustainable and efficient solar energy conversion systems. [ABSTRACT FROM AUTHOR]

Dye-sensitized solar cells (DSSCs) provide a promising alternative to traditional solar technologies, as they offer a unique mix of cost-effectiveness, adaptability, and the possibility of achieving high efficiency. This study aims to investigate the effect of SiO2 purity obtained from coal fly ash on the photoelectric performance of DSSCs. The study focuses on varying the purity of extracted SiO2 from coal fly ash as a counter-electrode material and examining its impact on the efficiency of DSSCs. The efficiency of DSSCs was assessed by evaluating the performance of several various SiO2 purity materials for counter-electrode materials. The performance testing of DSSCs revealed that the counter electrode material, consisting of artificial SiO2 with a purity of 99.9%, achieved the highest efficiency of 0.0113%. Subsequently, DSSCs were fabricated using counter-electrode materials derived from coal fly ash with a purity of 52.91%. These DSSCs demonstrated an efficiency of 0.0076%. DSSCs utilizing SiO2 with a purity of 91.20% exhibited an efficiency of 0.0062%. Dye-sensitized solar cells utilizing a counter electrode material composed of SiO2 with a purity level of 72.54% demonstrated an efficiency of 0.0061%. The results showed that the level of SiO2 purity obtained from coal fly ash has a substantial impact on the photoelectric performance of DSSCs, since higher purity of SiO2 is associated with improved efficiency. [ABSTRACT FROM AUTHOR]

We report the synthesis of phosphorus (P)-doped reduced graphene oxide (P-rGO) using a hydrothermal method at 180°C for 7 h. Furthermore, the amorphous nature and phase purity of the hydrothermally synthesized P-rGO was studied by powder x-ray diffraction. The characteristic sheet-like surface structure of the P-rGO was confirmed by scanning electron microscopy. The presence of P in the P-rGO was authenticated by using energy-dispersive x-ray spectroscopy and photoelectron x-ray spectroscopy. The synthesized P-rGO was employed as a low-cost and Pt-free counter electrode material for the construction of dye-sensitized solar cells (DSSCs). The effect of annealing temperature on the construction of the DSSCs using P-rGO was also studied, and the highest power conversion efficiency of 6.3% and photocurrent density of 15.37 mA/cm2 were obtained at 200°C. The platinum counter electrode-based DSSCs exhibited the power conversion efficiency of 7.4%. The performance of the P-rGO counter electrode-based DSSCs was reasonable and can be further improved by developing novel device architectures. This work proposes the simple, eco-friendly, and Pt-free counter electrode for the construction of DSSCs with a decent performance. [ABSTRACT FROM AUTHOR]

This work is focused on fabricating a counter electrode (CE) for application in a dye-sensitized solar cell (DSSC). Cobalt manganese oxide (CoMn2O4) nanoparticles (NPs) and its nanocomposite with graphene were prepared by a hydrothermal method. The nanocomposites of cobalt manganese oxide with graphene as CoMn2O4/(graphene)x (where x = 0.2, 0.4, and 0.6) were synthesized as an electrode material, and a cell was fabricated for the x = 0.6 nanocomposite to investigate the activity for use in DSSCs. These nanocomposites were characterized by x-ray diffraction (XRD), scanning electron microscopy (SEM), energy-dispersive x-ray spectroscopy (EDX), and Fourier transform infrared (FTIR) spectroscopy. SEM analysis revealed the nature of the particles, and the average grain size was in good agreement with XRD results. EDX showed the ratio of the respective samples. The XRD pattern showed the hexagonal structure of CoMn2O4 NPs with an average size of 39.45 nm. The FTIR spectrum indicated O–H stretching bonds and the vibrational bending of MnO at the interstitial sites. For electrochemical analysis, cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS) were performed. Through CV analysis, an anodic peak current (Ipa) was observed at 41.42 µA, while the cathodic peak current (Ipc) was observed at −37.13 µA, and peak-to-peak separation (ΔEpp) = 0.31 V for CoMn2O4 NPs. For graphene, Ipa = 180.45 µA, Ipc = −230 µA, and ΔEpp = 0.25 V, while Ipa = 100.23 µA, Ipc = 80.65 µA, and ΔEpp = 0.16 V for the CoMn2O4/graphene (x = 0.6) nanocomposite, which also showed excellent electrocatalytic properties. The charge transfer mechanism on the surface of the electrode was found to have rapid oxidation–reduction behavior and can be used as an alternative to platinum as the CE in the DSSC. The CV analysis of the CoMn2O4/graphene (x = 0.6) nanocomposite-based DSSC showed that the Ipa current was observed at 26.85 mA, while the Ipc current was observed at −27.25 mA in the two-electrode system. The Rs values for CoMn2O4/graphene with x = 0.2, 0.4, and 0.6 were 142.80 Ω, 141.33 Ω, 135.18 Ω, and 131.18 Ω, respectively, as an electrode material. The exchange current density J = 2.13 × 10−3 A/cm2 was found using the charge transfer resistance value (Rct = 6.03 Ω cm2) and was verified by the Tafel curve. [ABSTRACT FROM AUTHOR]

The increasing demand for sustainable energy as a means to combat the impact of climate change is addressed via a novel concept in the present work. Herein presented are developed transferable encapsulated dye-sensitized solar cells, canonically "solar capsules", for photovoltaic applications on alternative surfaces, such as facades. The solar capsule assembly houses all the components necessary for photovoltaic energy conversion, enclosed within a semiconductor nanotubular array, making them truly unique in their construction. This capsule-style unit enables an easy transfer and draft onto a wide range of materials and surfaces for photovoltaic functionalization and applications. This type of dye-sensitized solar cell typically consists of transferred solar capsules and two additional electrodes. The design and construction of solar capsules means they have a high economic viability as they can seamlessly be up-scaled using commercially established techniques such as anodization and subsequent functionalization. This work demonstrates a working model of such transferable solar capsules by fabricating TiO2 nanotubes that are functionalized via facile dip- and spin-coating techniques in a wet lab at ambient conditions. These prototypes are characterized in bulk and are thoroughly investigated at the nanoscale for information on the chemical distribution of the constituents, as they may be influenced during the manufacturing process. [ABSTRACT FROM AUTHOR]

Engineering new photoanode materials to substantially improve the efficiency of natural dye-sensitized solar cells (DSSC-Ns) is a significant challenge in the field of DSSC-Ns. This study utilizes the doctor blade technique to develop novel photoanode materials based on mixtures with different proportions of TiO2 Hombikat UV100 and TiO2 P25, two nanometric powders with different grain sizes. The fabricated films were studied by X-ray diffraction, which revealed a dominant anatase phase in the structure, as was corroborated by Raman spectroscopy. The crystallite size of the materials was determined using the Scherrer method. Using optical measurements, we estimated the bandgap energy (Eg) of the photoanodes that varied in the samples at around 3 eV. The assembled solar cells demonstrated a significant efficiency of 4.87% in the TiO2 Hombikat UV100/TiO2 P25 sample with the proportion of 50–50% (HP50) of blended photoanode. This sample device exhibited a fill factor of 50.41%, an open circuit voltage (Voc) of 0.65 V, and a current density of 14.75 mA/cm2 for an active surface area of 0.19 cm2. The HP50 sample constituted highly efficient DSSC-Ns and photoanodes with lower open-circuit voltage in the series, while HP40 developed a Voc of 0.73 V, and HP30 developed a Voc of 0.70 V. [ABSTRACT FROM AUTHOR]

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Transition metal oxide semiconductors, noted for their stability and suitable bandgap, are promising photoanodes for water splitting. Surface engineering is critical to tackle issues like low carrier mobility and charge recombination, stemming from atomic arrangement and Fermi level differences. While exposing dominant crystal facets boosts photocatalytic capability, it can hinder carrier injection into the electrolyte. In this study, BiVO4 films with various facet exposures were synthesized and characterized using scanning electron microscopy and x-ray diffraction to confirm their morphology and crystalline structure. Mott–Schottky analysis was employed to investigate changes in the band structure near the semiconductor–electrolyte interface, revealing that high (010)-BiVO4 facet exposure enhances carrier separation but reduces injection efficiency. The results from photoconductive atomic force microscopy tests demonstrated that enhanced band bending at the semiconductor interface improves hole transfer. Coating the (010)-BiVO4 photoanode with MoS2 and an amorphous ZrO2 interlayer yielded a photocurrent density of 0.6 mA cm−2 at 1.2 V (vs RHE) under AM 1.5 G illumination, tripling the pristine photoanode's performance and nearly tripling water splitting efficiency. Mechanism revealing the improved photoelectrochemical performance is attributed to a greater band bending on the BiVO4 surface, enhancing hole injection dynamics. This work provides a feasible strategy for a deeper understanding of the intrinsic mechanisms of facet engineering and improving the activity of photoanodes. [ABSTRACT FROM AUTHOR]

This study presents a significant advancement in tandem dye-sensitized solar cells (T-DSSCs) through the strategic synthesis of novel triazatruxene (TAT) sensitizers MS-1 and MS-2. These organic sensitizers demonstrate exceptional light-harvesting capacity and overall performance, pushing the boundaries of power conversion efficiency (PCE) in DSSCs. The MS-1-based DSSCs achieved an impressive PCE of 12.81%, while MS-2 sensitizers reached a notable 10.92%. These efficiencies represent significant improvements over the conventional N719 dye (7.60%), demonstrating the potential of metal-free organic sensitizers in DSSC technology. The key to these noteworthy results lies in the molecular design of the organic sensitizers. The triazatruxene donor segment in the MS-1 and MS-2 dyes, featuring a rigid structure and efficient intramolecular charge transfer (ICT), proved to be a game-changer for photovoltaic properties. Building on these results, we explored an innovative parallel tandem cell (PT-DSSC) configuration. By connecting separate cells containing N719 and MS-1 sensitizers, we achieved a record efficiency of 12.89% with enhanced short-circuit current density (JSC) and open-circuit voltage (VOC)compared to single-dye cells. This study highlights the potential of molecular engineering in organic sensitizers and device optimization to enhance DSSC performance, paving the way for further advancements in solar cell technology. [ABSTRACT FROM AUTHOR]

In this work, we evaluate the bonding characteristics and interfacial electron transfer dynamics of three heteroleptic ruthenium photosensitizers featuring different terpyridine (tpy) acceptor end configurations through quantum-chemical calculations. These photosensitizers feature tpy ligands with a mono/tricarboxylic acid or a phenyl-carboxylic acid anchor and a trans-disposed –NCS and N-heterocyclic carbene ligand in a C^N donor set. Adiabatic transitions reveal significant overlap between higher-excited and ground-state orbitals and correlate with the experimentally observed anti-Kasha fluorescence. In all complexes, two carboxylate-O atoms of the central anchor effectively bind with TiO2 by bridging two titanium sites. However, appending an additional anchor on each peripheral pyridine of tpy renders binding through only one anchor's –C＝O atom to TiO2. Contrary to the complex bearing three anchors, those featuring monocarboxylate-functionalized tpy exhibit faster electron injection within 100 fs. In all, this study provides insights into the photosensitization attributes of the ruthenium complexes for dye-sensitized solar cells. [ABSTRACT FROM AUTHOR]

ABSTRACT The synergistic influence of the LSPR (localized surface plasmon resonance) of gold nanoparticles (Au NPs) and the effect of nitrogen and chlorine co‐doped carbon dots (Cl/N‐CQDs) on dye‐sensitized solar cells (DSSCs) performance are investigated. The gold NPs are coated with a thin layer of Cl/N‐CQDs to produce the Au@Cl/N‐CQDs structure. DSSCs are fabricated by using Au@Cl/N‐CQDs as co‐sensitizer. The focus of this work is to examine the effects of plasmonic Au NPs and carbon dots in addition to their synergistic effect by capping the Au NPs with Cl/N‐CQDs, and track their influence in DSSCs. N719 as ruthenium‐based dye, and natural dyes including betanin, crocin, carthamin, curcumin, chlorophyll, mallow, and lawsone are selected and applied in the DSSCs co‐sensitized by Au@Cl/N‐CQDs. The power conversion efficiency (PCE) of DSSCs using all of the selected dyes is enhanced upon using the Au@Cl/N‐CQDs. It is due to the improvement in VOC (open circuit voltage) and JSC (short circuit photocurrent densities) relative to the use of dyes alone. Based on computational results, Au@Cl/N‐CQDs cause a red‐shift in comparison with pure dyes. The TD‐DFT (time‐dependent density functional theory) results show that the orbitals from the Au@Cl/N‐CQDs in dye/Au@Cl/N‐CQDs have contribution in most of the absorptions. In other words, electrons from HOMO (highest occupied molecular orbital) of Au@Cl/N‐CQDs is transferred to the LUMO (lowest unoccupied molecular orbital) of dye, in most cases. [ABSTRACT FROM AUTHOR]

Light harvesting materials are crucial for capturing the sunlight in a device such as a solar cell for better efficiency. In this study, we developed high surface area, submicron-sized TiO2 spheres (MTS) incorporated with anisotropic Au nanoparticles (Au_MTS) to create highly light-absorbing photoanodes for enhanced dye-sensitized solar cell (DSSC) efficiency. The high surface area of MTS (~125 m2/g) allows for increased dye-loading, while their submicron size (150-300 nm) provides superior light-scattering capabilities for significantly enhancing the photoanode's light absorption. Furthermore, incorporating of anisotropic Au nanoparticles enables broadband surface plasmon resonance (SPR) coupling, synergistically boosting photon harvesting in the Au_MTS photoanodes. The interconnected tiny TiO2 nanoparticle network in MTS supports charge carrier generation and transport, providing ample sites for dye adsorption and efficient electron pathways. Au_MTS with varying amounts of Au nanoparticles synthesized by a greener microwave-assisted synthesis method and DSSC devices were fabricated and compared with devices made from pristine MTS and P25 nanoparticles. The optimal Au_MTS device, containing ~1.3 wt% Au nanoparticles, achieved a maximum power conversion efficiency (PCE) of ~7.7%, representing improvements of ~40% and ~60% over pristine MTS (PCE of ~5.2%) and P25 nanoparticles (PCE of ~4.71%), respectively. Overall, this work demonstrates the effectiveness of plasmonic mesoporous photoanodes in enhancing DSSC performance through improved photo response, light scattering, and dye loading. [ABSTRACT FROM AUTHOR]

Tin oxide (SnO2) nanostructure thin film was synthesized on glass and FTO glass substrates at 450∘C with flow rates of Argon and oxygen (8L/h) using the atmospheric pressure chemical vapor deposition (APCVD) method. The surface morphology, structure and optical properties of SnO2 film were depicted by Field Emission scanning electron microscopy (FE-SEM), X-ray diffraction (XRD) and UV–Visible (UV–Vis) spectroscopy, respectively. The optical band gap of SnO2 film was found to be 3.72eV. In addition, a layer of titanium oxide was deposited on the SnO2 film using a screen printing method. Then, the anodic electrode was immersed in the dye to complete cell manufacturing. It was found that the short circuit current, open circuit voltage and fill factor in the case of the prepared dye-sensitized solar cell (DSSC) were 8.7mA/cm2, 0.85V and 0.583, respectively, which led to the efficiency of 4.3. It was also found that the optical response speed of the prepared photoanode showed a periodic response and a high on/off ratio. [ABSTRACT FROM AUTHOR]

The versatile absorption and fluorescence properties alongside the outstanding chemical and photostability make the rylene‐based derivatives one of the most investigated compounds in the field of third‐generation solar cells. Over the last 25 years, an intensive research activity has made the rylene‐based derivatives one of the most interesting and modular class of sensitizers in the dye‐sensitized solar cells. This critical analysis compares and discusses the state of the art of the rylene‐based dyes, starting from the pioneering studies on the perylene bisimides to the latest N‐annulated rylene derivatives. The focus of this review is to discuss the structure‐to‐properties relationship highlighting how critical points have been overcome and what are the most recent approaches toward the achievement of novel record efficiencies in the dye‐sensitized solar cells. [ABSTRACT FROM AUTHOR]

A series of N1-[4-(diethylamino)phenyl]-N4,N4-diethyl-N1-(thiophen-2-yl)benzene-1,4-diamine based (D-A2-π-A) organic dye-sensitizers with enzothiadiazole (DSN dyes)/dihydrothieno[3,4-b][1,4]dioxine (DSO dyes) as auxiliary acceptor were studied, emphasizing the influence of the π bridges on the DSSC's efficiency. DFT and TD-DFT methods at B3LYP/6-31G** were used to calculate the molecular, optoelectronic and photovoltaic properties of the dyes such as Frontier orbital energies, chemical reactivity indices, absorption wavelengths, light harvesting efficiency (LHE), electron injection driving force (ΔGinject), regeneration drive force (ΔGregen), open circuit voltage (Voc) and excited state lifetime (τesl). The results of open circuit voltage (Voc), light harvesting efficiency (LHE) and light electron injection driving force (ΔGinject) show that all the dyes have good photoelectric conversion efficiency but with low dye regeneration (ΔGregen) ability. The energy gap (Eg) has a major effect on the activity of molecules; thus, a sensitizer with a small Eg is more advantageous for electron excitation and has increased absorption properties. It was found that DSN dyes have lower Eg than corresponding DSO dyes. Therefore, DSN dyes are expected to have longer absorption wavelength (red shift) than respective DSO dyes. The DSN dyes show ease of electrons transfer through the dyes, which is linked to low values of chemical potential for DSO dyes. However, high excited state lifetime (τesl) values of some dyes could lead to more stability of the dyes in the cationic state for a longer time, which may result in higher charge transfer efficiency; thus enhancing electron injection efficiency of the dye sensitizers for dye-sensitized solar cell (DSSC). [ABSTRACT FROM AUTHOR]

Tungsten-doped TiO2 thin films were prepared by sol–gel method on fluorine-doped tin oxide-coated substrates as working electrodes of dye-sensitized solar cells. The influences of different W doping (0, 2, 4, 6, and 8 at%) on the microstructure, optical, and photovoltaic properties of the W-TiO2 thin-film DSSCs were studied by the measurement of X-ray diffraction (XRD), scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS), Brunauer–Emmett–Teller (BET) analysis, and electrochemical impedance spectroscopy (EIS). An optimal DSSCs performance was observed with a 6 at% W-doped TiO2 thin film, resulting in a Voc of 0.68 V, a Jsc of 20.2 mA/cm2, an FF of 68.6%, and an efficiency (η) of 9.42%. The efficiency of DSSCs with 6 at% W-doped TiO2 photoanode improved by 75%. This is because the 6 at% W-doped TiO2 thin film increases the specific surface area and electron transfer rate. [ABSTRACT FROM AUTHOR]

We developed dye-sensitized solar cells (DSSCs) using 1,5-carboxy-2-[[3-[(2,3-dihydro-1,1-dimethyl-3-ethyl-1H-benzo[e]indol-2-ylidene)methyl]-2-hydroxy-4-oxo-2-cyclobuten-1-ylidene]methyl]-3,3-dimethyl-1-octyl-3H-indolium and 1,3,3-trimethyl indolino-6′-nitrobenzopyrylospiran. The DSSCs incorporate photochromic molecules to regulate photoelectric conversion properties. We irradiated photoelectrodes adsorbed with SQ2/SPNO2 using both UV and visible light and observed the color changes in these photoelectrodes. Following UV irradiation, the transmittance at 540 nm decreased by 20%, while it increased by 15% after visible light irradiation. This indicates that SPNO2 on the DSSCs is photoisomerized from the spiropyran form (SP) to the photomerocyanine (PMC) form under UV light. The photoelectric conversion efficiency (η) of the DSSCs increased by 0.15% following 5 min of UV irradiation and decreased by 0.07% after 5 min of visible light irradiation. However, direct electron injection from PMC seems challenging, suggesting that the mechanism for improved photoelectric conversion in these DSSCs is likely due to Förster resonance energy transfer (FRET) from PMC to the SQ2 dye. The findings suggest that the co-sensitization of DSSCs by PMC-SQ2 and SQ2 alone, facilitated by their respective photoabsorption, results in externally responsive and co-sensitized solar cells. This study provides valuable insights into the development of advanced DSSCs with externally controllable photoelectric conversion properties via the strategic use of photochromic molecules and energy transfer mechanisms, advancing future solar energy applications. [ABSTRACT FROM AUTHOR]