Design Of Solar Cells Research Articles

Achieving bifacial photovoltaic performance in PTB7-based organic solar cell by integrating transparent contact for emerging semi-transparent applications

In this study, the design, fabrication and detailed analysis of semi-transparent bifacial organic solar cells (ST-OSC) based on MoO3/Ag/WO3 (10/dm/dod nm) dielectric/metal/dielectric (DMD) transparent contact system integrated with PTB7 polymer were investigated. The study emphasizes the importance of designing transparent contact systems to optimize the solar cells’ transparency (average visible transmittance, AVT), color rendering (color rendering index, CRI), efficiency (power conversion efficiency, PCE), and bifaciality. The performance of three distinct configurations was examined in the AVTmax (47.14% AVT, 3.93% PCE), (CRIext)max (23.82% AVT, 6.21% PCE), and Extreme Color (26.34% AVT, 5.81% PCE). The theoretically predicted AVTs for these configurations were 48.75%, 22.29%, and 25.15%, respectively. The strong agreement between theoretical and observed outcomes confirmed the accuracy of the Transfer Matrix Model (TMM). Furthermore, the assessment of bifaciality performance exhibited that the AVTmax had a bifaciality factor of 0.94, with a PCE of 3.67% under top illumination and 3.93% under bottom illumination. The high bifaciality of the structure designed with TMM to maximize the AVT demonstrates the value of calculations prior to solar cell structure fabricating and the possibility of constructing high bifaciality structures using this technique.

Improving current-matching in textured perovskite/silicon tandem solar cells via a thickness control strategy

This study presents an analysis of a two-terminal tandem solar cell that integrates metal-doped, lead-free double Cs2AgBi0.75Sb0.25Br6 perovskite with silicon to enhance overall energy conversion efficiency. This study explores how the thicknesses of the top and bottom sub-cells affect current-matching in two-terminal tandem perovskite/silicon solar cells with two separate planar and textured configurations. Using numerical modeling in MATLAB, and considering dominant recombination effects, we calculated the performance parameters of the device. We investigated the optical and electrical properties of textured tandem structures, focusing on current- matching and the influence of layer thickness on device performance. Given the complexity, time, and expense involved in constructing tandem solar cells, being able to analytically determine the thickness at which current-matching occurs can be highly advantageous. This approach offers the benefit of providing a precise analytical relationship for this purpose. Our findings demonstrate that increasing the top cell thickness enhances current density and power conversion efficiency, but at the cost of the bottom cell’s efficiency due to increased light absorption. Moreover, we discovered a nearly linear behavior between the thickness of the top and bottom cells for achieving current-matching. The study highlights the critical balance required to optimize layer thicknesses, thereby improving the design and performance of tandem solar cells. These insights are significant as they pave the way for more efficient and cost-effective tandem solar cell designs in the future, potentially accelerating the adoption of advanced photovoltaic technologies. The results show good agreement with experimental data, validating our model.

Atomistic insight into the device engineering of inorganic halide perovskite solar cells

Perovskites provide a promising pathway for fabricating efficient and lightweight solar cells, which could be game-changers in the renewable energy landscape. Yet, the phase stability and device design are still the key issues of perovskite-based photovoltaics. Herein, we evaluated the phase stability of CsPbX3 (X = I, Br, and Cl) upon analyzing the lattice dynamics from first-principles and then predicted fundamental properties including bandgap, carrier mobility, and optical absorption as input to optimize the device design of solar cell. A maximum power conversion efficiency (PCE) of 12.36 % was achieved for a CsPbBr3-based solar cell. Those findings highlight the potential of CsPbX3 perovskites for high-efficiency solar cells. The computational approach provides a comprehensive understanding of the material's structural stability, charge-carrier dynamics, and optoelectronic characteristics. The collective analysis enables a holistic understanding of CsPbX3 perovskites and provides a roadmap for future advancements in perovskite solar-cell technology.

Predictive Modeling and Design of Organic Solar Cells: A Data-Driven Approach for Material Innovation

Predictive Modeling and Design of Organic Solar Cells: A Data-Driven Approach for Material Innovation

Understanding the optoelectronic and vibrational properties of MB[formula omitted]O[formula omitted], using density functional theory, where M = Yb or Ce

This work aims to use density functional theory (DFT) and density functional perturbation theory (DFPT) to study the structure, optoelectronics, phonon dispersion and energetic stability of two new tetraborates, MB4O7, where M = Yb or Ce. The estimated values of the band gap energy (Eg) and power conversion efficiency (PCE) for the systems were calculated. The Shockley-Queisser was also taken into account to measure the maximum theoretical efficiency of a photovoltaic source cell based on a p-n union. The estimated average gap energy values for the YbB4O7 and CeB4O7 systems, calculated using the GGA-PBE, HSE06, and GGA+U functionals, were 3.64 eV and 0.97 eV, respectively. The average PCEs calculated for the YbB4O7 and CeB4O7 systems were 11.28% and 25.66%, respectively. The PCE and energy stability suggest that CeB4O7 may be a more viable candidate for a solar device than YbB4O7, at least in terms of these specific parameters. The results reported here, as well as those related to absorption calculations, showed that the structures have optical responses in the visible region, suggesting that both systems can be used as optoelectronic devices and in solar cell designs.

Tunable optical properties of BAs/ZnO vdW heterostructure

Stacked heterostructures is an effective strategy for physical property modulation and application of novel two-dimensional materials. In this study, a heterostructure consisting of two-dimensional III-V group hexagonal BAs and monolayer of ZnO is presented. The minimum value of binding and cohesive energies screened the BB’ configuration. Phonon spectra and ab initio molecular dynamics (AIMD) simulations further demonstrated the kinetic and thermodynamic stability of the selected model. Most notably, the formation of the heterostructure greatly improves the optical absorption performance of the monolayer, especially in the infrared (IR) regions. At a compressive strain of −6%, the band alignment shifts from type I to type II, while the bandgap becomes dramatically smaller. Refraction and reflection coefficients in the IR region under compressive strain (−2% and −4%) modulation were enhanced significantly. Our results provide theoretical guidance for the design of high-performance photovoltaic devices and solar cells based on BAs/ZnO heterostructures.

An Optimized Design of Cd-free CZTS Solar Cells Using High-Performance Electron Transport Materials to Minimize Recombination Effects

An Optimized Design of Cd-free CZTS Solar Cells Using High-Performance Electron Transport Materials to Minimize Recombination Effects

On the performance and thermal stability of solar cell based on CIGS-Sb2S3 combination with >35% power conversion efficiency

This study presents a solar cell design utilizing a CIGS (copper-indium-gallium-selenide) absorber and Sb2S3 (antimony trisulfide) back surface field (BSF) layers, targeting high photovoltaic (PV) performance with an emphasis on minimum possible effect of ambient temperature. We simulated a solar cell design consisting of zinc oxide, surface defect layer, zinc sulfide, CIGS layer, and an Sb2S3 layer using SCAPS-1D software. Our findings indicate that 200 nm Sb2S3 layer and a 1600 nm CIGS layer is the preferred combination for achieving high PV performance and appropriate J-V characteristics of the proposed solar cell. For this design, the achieved values of VOC (open circuit voltage), JSC (short circuit current density), PCE (power conversion efficiency), and fill factor (FF) are 1.069V, 42.08 mA/cm2, 35.94%, and 80.31%, respectively. The PV performance of the proposed solar cell is substantially better than the solar cell design without BSF layer as well as recently reported (2023-24) solar cell designs. This study further examines the impact of elevated ambient temperatures (295–360 K) on the PV performance. Our simulation results show that operating the proposed solar cell at moderately elevated temperatures is not a significant issue owing to small power temperature coefficient (-0.034% per K), which is comparable to that of commercially available solar cells. These findings are expected to contribute to the ongoing advancement of PV solar cells, aiming for higher PCE and improved stability, including thermal stability. Proposed solar cell with low PTC and high PCE can be suitable for space applications where temperature fluctuation is severe, as well as in tropical areas.

Influence of Composition on Mechanical Properties and Sound Speed of AlAs1−xPx for Various Pressures

The mechanical properties of AlAs1−xPx alloy under the influence of composition have been determined. The sound speed of AlAs1−xPx has been determined at various compositions. The studied properties were obtained with the effect of composition at various pressures. The predicted values were consistent with the available experimental results. The investigation used empirical method calculations based on empirical pseudo potential theory (EPM) with the virtual crystal approximation (VCA) to broaden the applications of ternary alloys and better investigate their potential as novel materials. AlAs1−xPx is a material that shows promise for usage in multi-junction solar cell designs because its properties can potentially be adjusted. The mechanical stability of AlAs1−xPx alloys was obtained according to these conditions C11 + 2C12 > 0, C44 > 0, and C11-C12 > 0. The obtained anisotropy factor was not equal to 1, indicating the presence of elastic anisotropy in the studied alloy in the applied composition range. The AlAs1−xPx alloy is a ductile material throughout the entire composition range at various pressures due to the Bu/Cs values exceeding 1.75.

Spectral Control by Silver Nanoparticle-Based Metasurfaces for Mitigation of UV Degradation in Perovskite Solar Cells.

Perovskite solar cells are considered to be one of the most promising solar cell designs in terms of photovoltaic efficiency. However, their practical deployment is strongly affected by their short lifetimes, mostly caused by environmental conditions and UV degradation. In this contribution, we present a metasurface made of silver nanoparticles used as a UV filter on a perovskite solar cell. The UV-blocking layer was fabricated and morphologically and compositionally analyzed. Its optical response, in terms of optical transmission, was also experimentally measured. These results were compared with simulations made through the use of a well-proven computational electromagnetism model. After analyzing the discrepancies between the experimental and simulated results and checking those obtained from electron beam microscopy and electron dispersion spectroscopy, we could see that a residue from fabrication, sodium citrate, strongly modified the optical response of the system, generating a redshift of about 50 nm. Then, we proposed and simulated the optical behavior of core-shell nanoparticles made of silver and silica. The calculated spectral absorption at the active perovskite layer shows how the appropriate selection of the geometrical parameters of these core-shell particles is able to tune the absorption at the active layer by removing a significant portion of the UV band and reducing the absorption of the active layer from 90% to 5% at a resonance wavelength of 403 nm.

Boosting efficiency in dual-absorber RbPbBr3 perovskite solar cell: the role of two-dimensional GeS and SnS2 as electron transport layers

This paper presents a comprehensive investigation into the electrical characteristics of a perovskite solar cell. The n-i-p cell is based on a low band gap rubidium–lead-bromide (RbPbBr3) perovskite with an energy level of 1.31 eV. The study also evaluates the impact of high mobility two-dimensional GeS and SnS2 as electron transport layers (ETLs) on the cell’s performance. These ETLs have a wide band gap and provide a hole blocking layer due to their high valence band-offset. Additionally, a thin film MoTe2 with a band gap of 1 eV is considered as a complementary absorber for capturing near-infrared solar spectrum. The investigation focuses on the influence of critical physical and structural design parameters on the electrical parameters of the cell. The optimized device with SnS2 as the ETL exhibits a power conversion efficiency (PCE) of 25.03%, an open circuit voltage of 0.95 V, a short circuit current density of 33 mA cm−2, and a fill factor of 80.31%. Similarly, the device with GeS as the ETL achieves a PCE of 25.14%, an open circuit voltage of 0.96 V, a short circuit current density of 33.01 mA cm−2, and a fill factor of 80.66%. Furthermore, a statistical analysis is conducted by calculating the coefficient of variation to assess the sensitivity of the cell’s electrical measures to the variation of design parameters and operating temperature. The results highlight that defects in the absorber layer, work function of the back contact, and ambient temperature are critical design parameters that can significantly impact the device performance. Overall, the utilization of high mobility wide band gap ETLs, in combination with the low band gap perovskite, offers a promising approach for the design of high-performance solar cells.

Advanced High-Throughput Rational Design of Porphyrin-Sensitized Solar Cells Using Interpretable Machine Learning.

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.

Innovative designs for semitransparent carbon-based perovskite solar cells for building-integrated applications

Recently, semitransparent perovskite solar cells (SM-PSKs) have been developed, allowing part of the light to pass through the cell while absorbing the rest. Various strategies, including thinning the perovskite layer, innovative electrode materials, and incorporating plasmonic nanoparticles, have been explored, leading to efficiencies up to 14.78 % and transparency of 26.7 %. However, such cells face stability issues and are mostly fabricated in a controlled environment, limiting their scalability to module level and reducing their commercialization prospects. In contrast, carbon incorporation has shown potential for extending the lifespan of opaque PSKs, exhibiting remarkable stability of 1000 h and efficiencies exceeding 16 %. This study employs carbon-based perovskite solar cells fabricated using the screen printing technique with environmental conditions maintained at ambient levels for both temperature and humidity. The architecture of the cell is carefully modified to obtain several novel designs of semitransparent carbon-based perovskite solar cells (CSM-PSKs). UV–Vis spectroscopy tests are performed for each CSM-PSK, resulting in different average visible transparencies (AVT). The electrical properties of the opaque and proposed CSM-PSK designs are characterized using a Solar Simulator (Model: Solixon A-70-CU-2). Among the designs, one CSM-PSK demonstrates superior performance with an AVT of 8.65 % and a power conversion efficiency (PCE) of 5.6 %, highlighting their scalability for sustainable building-integrated energy solutions.

Formation of High-Photoresponsivity BaSi2 Films by Radio-Frequency Sputtering and Evaluation of a BaSi2/TiN/Glass Heterojunction by Transmission Electron Microscopy.

Barium disilicide (BaSi2) is a thin-film solar cell material composed of abundant elements, and its application potential is further enhanced by its formation on inexpensive substrates, such as glass. The effect of the substrate temperature on the co-sputtering of BaSi2 and Ba targets to form BaSi2 films on Si(111) and TiN/glass substrates was investigated. Contrary to expectations, the photoresponsivity reached maximum values exceeding 5 and 2 A W-1, respectively, the highest value ever reported for as-deposited samples formed at 750 °C, more than 100 °C higher than those reported previously. Because the photoresponsivity is proportional to carrier lifetime, this result indicates that high-temperature growth can bring out the high performance of BaSi2 as a light-absorbing layer. Because amorphous SiC (a-SiC) has a larger forbidden band gap and electron affinity than BaSi2, it is considered suitable as an electron transport layer (ETL) material for BaSi2 solar cells. On the basis of this, the formation of BaSi2 (absorption layer)/a-SiC (ETL)/TiN (electrode)/glass heterojunctions was also attempted, and the layered structure was examined by cross-sectional transmission electron microscopy (TEM). Polycrystalline BaSi2 films were found to be even on the amorphous layer by TEM. A high photoresponsivity of over 2 A W-1 was obtained. Therefore, the BaSi2/a-SiC/TiN structure provides a guideline for the structural design of BaSi2-based thin-film solar cells on glass.

Enhanced Design of Kesterite Solar Cells through High-Throughput Screening and Machine Learning Approaches.

Kesterite Cu2ZnSnS4 (CZTS) is regarded as one of the most promising materials for thin-film solar cells due to its high light absorption capability, composition of earth-abundant and nontoxic elements, and ease of low-cost mass production. Although the certified power conversion efficiency (PCE) of kesterite solar cells has exceeded 14%, this efficiency remains significantly below the Shockley-Queisser limit. In this study, we generated a Perdew-Burke-Ernzerhof (PBE) band gap data set encompassing 263 64-atom species for high-throughput screening by substituting elements at different sites in A2BCX4 quaternary kesterite materials. Additionally, we utilized a symbolic regression method based on genetic programming to explore the functional relationship among the oxidation state, ionic radius, and electronegativity of kesterites with PBE band gaps. Simultaneously, we employed decision tree models (XGBoost, LightGBM, CatBoost, and random forest) and convolutional neural network (CNN) models (CustomCNN, VGG16, DenseNet121, Xception, and EfficientNetV2B0) to predict band gaps, achieving a coefficient of determination (R2) of up to 0.93. Furthermore, we selected 54 kesterite materials with PBE band gaps ranging from 0.4 to 1.5 eV for detailed electronic structure calculations with Heyd-Scuseria-Ernzerhof (HSE06) functional and investigated the effects of B-site atomic substitutions on the performance of solar cell materials. Compared to Ag2CaSnSe4, Ag2SrSnSe4 exhibits fewer deep defects and richer shallow defects, which contribute to an increased carrier concentration and reduced charge and energy losses, making it a superior candidate for solar cell applications.

Performance optimization of a novel perovskite solar cell with power conversion efficiency exceeding 37% based on methylammonium tin iodide

The development of highly efficient lead-free solar cells is essential for sustainable energy production in the face of depleting fossil fuel resources and the negative effects of climate change. Perovskite solar cells (PSCs) containing lead pose considerable environmental and public health hazards, in addition to thermal stability and longevity challenges. Here, a novel lead-free solar cell design of the configuration, ITO/PC61BM/CH3NH3SnI3/PEDOT:PSS/Mo, is investigated for improved light harvesting capabilities, enhanced device performance, and better operational efficiency under various temperature conditions. The optimal thickness of the light-absorbing layer, CH3NH3SnI3, was found to be 1000 nm for maximum quantum efficiency (QE). Further, the temperature tolerance of the solar cell was evaluated using Mott-Schottky (MS) capacitance analysis and showed that the model cell retains about 95% of its power at 400 K, demonstrating excellent thermal stability and robust performance. The solar cell also shows promising electrical output parameters, including a short-circuit current density (Jsc) of 34.84 mA/cm², open-circuit voltage (Voc) of 1.5226 V, Fill factor (FF) of 71.04%, and an impressive power conversion efficiency (PCE) of 37.66% at 300 K. The effect of buffer layers such as CdS, ZnS, ZnSe, and V2O5 on the electrical outcomes of the model cell structure has been critically examined. Additionally, parasitic resistances and doping characteristics on the operational performance of the cell have been explored in detail. This work therefore, provides remarkable insights in the field of solar energy harvesting, offering potential sustainable energy generation solutions, supporting de-carbonization of the environment and climate change mitigation efforts towards an energy sustainable future.

Solar Cells on Multicrystalline Silicon Thin Films Converted from Low‐Cost Soda‐Lime Glass

AbstractFabrication and characterization of solar cells based on multicrystalline silicon (mc‐Si) thin films are described and synthesized from low‐cost soda‐lime glass (SLG). The aluminothermic redox reaction of the silicon oxide in SLG during low‐temperature annealing at 600 – 650 °C leads to an mc‐Si thin film with large grains of lateral dimensions in the millimeter range, and moderate p‐type conductivity with an average Al acceptor concentration between 5 × 1016 and 1.2 × 1017 cm−3 in the bulk. A residual composite layer of mainly alumina and unreacted Al forms beneath the mc‐Si thin film as the second product of the crystalline silicon synthesis (CSS) process, which can be used as rear contact in a vertical solar cell design. The mc‐Si absorber (≈10 µm) is thin enough that the diffusion length given by a minority carrier lifetime of ≈1 µs exceeds the path length to the top contact several times. Homojunction and heterojunction diodes have been fabricated on the mc‐Si thin films and show great potential of CSS for the realization of high‐performance solar cells.

Machine learning empowers efficient design of ternary organic solar cells with PM6 donor

Organic solar cells (OSCs) hold great potential as a photovoltaic technology for practical applications. However, the traditional experimental trial-and-error method for designing and engineering OSCs can be complex, expensive, and time-consuming. Machine learning (ML) techniques enable the proficient extraction of information from datasets, allowing the development of realistic models that are capable of predicting the efficacy of materials with commendable accuracy. The PM6 donor has great potential for high-performance OSCs. However, it is crucial for the rational design of a ternary blend to accurately forecast the power conversion efficiency (PCE) of ternary OSCs (TOSCs) based on a PM6 donor. Accordingly, we collected the device parameters of PM6-based TOSCs and evaluated the feature importance of their molecule descriptors to develop predictive models. In this study, we used five different ML algorithms for analysis and prediction. For the analysis, the classification and regression tree provided different rules, heuristics, and patterns from the heterogeneous dataset. The random forest algorithm outperforms other prediction ML algorithms in predicting the output performance of PM6-based TOSCs. Finally, we validated the ML outcomes by fabricating PM6-based TOSCs. Our study presents a rapid strategy for assessing a high PCE while elucidating the substantial influence of diverse descriptors.

Performance optimization of eco-friendly CH3NH3SnI3 based perovskite solar cell employing CH3NH3SnBr3 as hole transport layer by SCAPS-1D device simulator

This study focuses on the theoretical aspects of third-generation perovskite solar cells (PSC), with the aim of replacing traditional silicon-based counterparts. With potential for higher efficiency and low manufacturing costs, perovskite cells offer unique crystallographic structures allowing adjustments to photoluminescence wavelength. This research addresses challenges in cost-effective solar spectrum utilization and optimization of parameters, device architecture, and materials for high-efficiency cells. In this study, we simulated a perovskite-based solar cell (CH3NH3SnI3) using solar cell capacitance simulator-one dimension simulator under AM 1.5G illumination. The chosen electron transport layer is TiO2, and hole transport layer is CH3NH3SnBr3. The simulation explores variations in layer thickness, defect concentration, interface defects, doping concentration and electron affinity. Additionally, we analyzed the impact of back metal contact work function and temperature variations. Results indicate optimal absorber layer thickness at 0.5µm. Reduced defect concentrations, increased doping concentration and a higher work function for the back contact, enhance efficiency of PSC. The initial parameters yielded a 19.79% efficiency based on base values before optimization, which increased to 26.66% after optimization. According to the latest NREL data, the highest reported efficiency for PSC is 26.1%. This research provides insights into perovskite-based solar cell design for enhanced efficiency.

Design and simulation of bifacial perovskite solar cell with high efficiency using cubic plasmonic nanoparticles

Bifacial perovskite solar cells (Bi-PSCs) are gaining attention for their ability to exceed the efficiency limits of traditional single-junction cells by absorbing light from both the front and rear surfaces. This study explores a novel approach to boost the efficiency and stability of Bi-PSCs by integrating clusters of cubic metallic nanoparticles (NPs) within the absorber layer. These plasmonic NPs, embedded in the middle of the absorber layer, significantly enhance light absorption, resulting in substantial improvements in power conversion efficiency for both front and rear irradiation. Our three-dimensional simulations demonstrate that incorporating Ag-based NPs can achieve efficiency enhancements of 29.89 % (from 18 % to 23.39 %) for front irradiation and 29.63 % (from 17.22 % to 22.33 %) for rear irradiation. Ag-based NPs exhibit the most notable efficiency improvement, reaching a short-circuit current of 41.30 mA/cm2 and an efficiency of 35.34 % at an albedo of 0.5. To address potential issues such as corrosion and degradation of the perovskite material, the metallic NPs are encapsulated with a thin dielectric nano-shell of SiO₂. This encapsulation strategy effectively prevents degradation, ensuring the long-term stability of the Bi-PSCs. The results indicate that the use of clusters of cubic metallic NPs, combined with dielectric encapsulation, offers a superior approach to optimizing the performance and stability of Bi-PSCs, providing a more efficient alternative to increasing the absorber layer’s thickness.