Characteristics Of Solar Cells Research Articles

The origins of nonlinear peculiarities on the IV characteristics of multi-junction solar cells

The paper presents an overview of studies of the multi-junction (MJ) solar cells (SC) with IV characteristics having nonlinear peculiarities. It is shown that such peculiarities can arise either due to hetero-interface barriers (HB) for majority charge carriers or due to problems with tunnel diodes (TD). It is usually difficult to identify which of these hetero-structural objects is the cause of this nonlinearity, since the peculiarities appear similarly in the IV characteristics of MJ SC. The experimental method presented in this work is based on the study of IV characteristics during the overheating of MJ SCs. The behavior of nonlinear peculiarities caused by an imperfect TD or an HB is fundamentally different during the overheating of SCs, which makes it possible to identify the type of hetero-structural object. Since the number of hetero-interfaces in MJ SC is large, a method determining the position of problematic objects in the MJ structure was also developed. The method is based on the illumination of individual subcells using different laser wavelengths. Both methods considered were tested experimentally on GaInP/GaAs/Ge SCs.

Innovative design strategies for solar cells: Theoretical examination of linearly graded perovskite solar cell with PTAA as HTL

Over the previous few decades, numerous scientific and theoretical approaches have been employed to increase solar cell efficiency. To improve PV cell efficiency, this study employs grading methodologies and modifies temperature, series resistance, different defect densities, and graded layer thickness. The paper presents a theoretical examination of the linearly graded device structure (Au/PTAA/CsPbBr3-xIx/TiO2/FTO). A linearly graded perovskite layer, responsible for absorbing a wide range of light spectra with different wavelengths, assists in bettering the solar cell's characteristics. In this device, polytriarylamine (PTAA) acts as an HTL, and TiO2 acts as an ETL. SCAPS-1D, a simulation program, is used for our theoretical analysis. The output results obtained from the simulation are as follows: PCE of 20.50 %, JSC of 18.071 mA cm−2, VOC of 1.4531 V, and FF of 78.08 %.

Fabrication and Characterization of Co-Sensitized Dye Solar Cells Using Energy Transfer from Spiropyran Derivatives to SQ2 Dye

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.

ANALYTICAL MODEL OF LIGHT CURRENT-VOLTAGE CHARACTERISTICS OF A SOLAR CELL BASED ON EXPERIMENTAL DATA

In this work, a modified experimental method for calculating the parameters of the one-exponential equation of the light current-voltage characteristic of solar cells has been developed using approximation and verification of experimental data. This approach allowed us to create a more accurate mathematical model of such characteristics. It has been confirmed that the approximation equation of the open circuit voltage versus short circuit current contains the necessary data to establish the numerical values of the p-n junction parameters: the imperfection factor and the saturation current of the one-exponential model of the light current-voltage characteristics of a solar cell. A comparison between the experimentally measured results and those predicted by the mathematical model results allowed not only to correctly determine the values of the parameters of the one-exponential equation of light current-voltage characteristics, but also to identify instrumental and computational errors in the experimental studies. An expression for calculating the series resistance based on verified current and voltage values at the point of maximum power was derived. In cases where the current or voltage values at the maximum power point are questionable, the determination of the series resistance value is possible using numerical methods for solving the equation of the single-exponential model in a narrow range of the light current-voltage characteristic curve in the vicinity of the maximum power point. The use of algorithms in maximum power point tracking systems that more reliably determine its coordinates increases the efficiency of these systems and the output power delivered to the load.

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.

Fabrication and characterization of bulk heterojunction organic solar cell: a review

Fabrication and characterization of bulk heterojunction organic solar cell: a review

Atom layer deposited TiO2 electron transport layer for silicon heterojunction solar cells to achieve high performance

Silicon/compound heterojunction (SCH) solar cells based on p-type and n-type c-Si wafers using atom layer deposition-TiO2 and low work function metal as the electron transport layer and rear electrode are fabricated. Efficiencies of 20.6 % and 21.6 % are achieved on p-type and n-type silicon solar cells, respectively. High Voc exceeding 700 mV have been realized on both kinds of Si wafers. Special attention has been paid to the SCH solar cells based on p-type c-Si wafers in which the TiO2 electron transport layer serves as the emitter. Carrier transport mechanisms and junction characteristics of the SCH solar cells are analyzed based on dark J-V measurement. The formation of a strong inversion layer at the Si surface region is determined, which implies the high Voc potential of the SCH solar cells based on p-type Si. An optical loss analysis is performed along with a possible solution to further improve the Jsc. The feasibility of TiO2 applied as an efficient electron transport layer (emitter) in p-type SCH solar cells with high performance has been showed.

Recent Progress and Applications of NanoIR‐AFM in Morphological Characterization of Organic Solar Cells

AbstractOrganic solar cells (OSCs) are gaining attention in building‐integrated and agricultural photovoltaics due to their light weight, mechanical flexibility, and low‐cost solution processability. To achieve commercial viability, understanding the relationships between active layer material structure, film morphology, and photovoltaic performance is crucial. Nanoscale infrared spectroscopy coupled with atomic force microscopy (nanoIR‐AFM) offers an advanced characterization of active layer morphology at high resolution to help understand OSC performance. This review outlines recent developments and applications of nanoIR‐AFM in OSC research, detailing its principles, instruments, and functions. Strategies to enhance OSC performance and their morphological characterization by nanoIR‐AFM are discussed, offering insights into active layer evolution and device performance. The review highlights challenges faced by nanoIR‐AFM in OSC applications and highlights its potential role in advancing OSC technology. As nanoIR‐AFM continues to evolve, it will play a critical role in OSC development, providing essential technical means for further progress.

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.

A Review of CIGS Thin Film Semiconductor Deposition via Sputtering and Thermal Evaporation for Solar Cell Applications

Over the last two decades, thin film solar cell technology has made notable progress, presenting a competitive alternative to silicon-based solar counterparts. CIGS (CuIn1−xGaxSe2) solar cells, leveraging the tunable optoelectronic properties of the CIGS absorber layer, currently stand out with the highest power conversion efficiency among second-generation solar cells. Various deposition techniques, such as co-evaporation using Cu, In, Ga, and Se elemental sources, the sequential selenization/sulfidation of sputtered metallic precursors (Cu, In, and Ga), or non-vacuum methods involving the application of specialized inks onto a substrate followed by annealing, can be employed to form CIGS films as light absorbers. While co-evaporation demonstrates exceptional qualities in CIGS thin film production, challenges persist in controlling composition and scaling up the technology. On the other hand, magnetron sputtering techniques show promise in addressing these issues, with ongoing research emphasizing the adoption of simplified and safe manufacturing processes while maintaining high-quality CIGS film production. This review delves into the evolution of CIGS thin films for solar applications, specifically examining their development through physical vapor deposition methods including thermal evaporation and magnetron sputtering. The first section elucidates the structure and characteristics of CIGS-based solar cells, followed by an exploration of the challenges associated with employing solution-based deposition techniques for CIGS fabrication. The second part of this review focuses on the intricacies of controlling the properties of CIGS-absorbing materials deposited via various processes and the subsequent impact on energy conversion performance. This analysis extends to a detailed examination of the deposition processes involved in co-evaporation and magnetron sputtering, encompassing one-stage, two-stage, three-stage, one-step, and two-step methodologies. At the end, this review discusses the prospective next-generation strategies aimed at improving the performance of CIGS-based solar cells. This paper provides an overview of the present research state of CIGS solar cells, with an emphasis on deposition techniques, allowing for a better understanding of the relationship between CIGS thin film properties and solar cell efficiency. Thus, a roadmap for selecting the most appropriate deposition technique is created. By analyzing existing research, this review can assist researchers in this field in identifying gaps, which can then be used as inspiration for future research.

Impedance dynamics in tandem solar cells based on c-Si with upper layers of CsPbBr3 (CsPbI3) perovskite nanocrystals

The application of an additional nanoparticle layer is a common practice for enhancing the optical and electrical properties of third-generation solar cells. In this study, we present the results of impedance spectroscopy (IS) for modified solar cells using Nyquist and Bode diagrams. The structure investigated consists of a conventional double junction based on crystalline silicon (c-Si) coated with thin films of inorganic perovskite nanocrystals (NC) of lead halides CsPbI3 and CsPbBr3. The latter are characterized by a significant phonon disorder, which leads to unique electron-phonon interactions and dielectric responses. The IS results indicate that, under the same conditions, the measured Nyquist plots align well with the simulated ones. An equivalent circuit model is proposed, featuring ohmic resistance, recombination resistance, and geometric capacitance. These elements arise due to charge accumulation, charge transfer resistance, and/or additional interfacial electronic states. The study finds that the introduction of a CsPbI3 layer enhances the photoresponse under bias conditions, but this photoresponse leads to a decrease in DC conductivity. In contrast, the addition of a CsPbBr3 layer obstructs the photoresponse under bias while slightly improving the photoresponse in the absence of an applied voltage. The results obtained contribute to the improvement of tandem solar cell characteristics featuring top layers of perovskite nanocrystals.

Characterization of fully-evaporated perovskite solar cells and photodetectors under high-intensity pulsed proton irradiation

This study investigates the impact of proton irradiation on perovskite devices fabricated fully through vacuum deposition. Exposure to irradiation induces changes in both electrical and optical properties. The analysis reveals that the main factors influencing the observed performance changes in solar cells are a significant reduction in shunt resistance and a minor increase in series resistance, with minimal alterations in recombination dynamics. Remarkably, the devices maintain promising photodetector characteristics both before and after proton irradiation, particularly in a self-powered mode without a reverse bias. These findings provide valuable insights into the resilience of vacuum-deposited perovskite devices against ionizing radiation, highlighting their potential for applications in radiation-prone environments, such as the nuclear industry or space exploration.

K2Ag(Ga/In)Br6 lead-free HDPs: Investigation of the elastic, optoelectronic, optical coating, and thermal characteristics for thermoelectric and solar cells

In this study, an investigation of the structural stability, elastic, optoelectronic, thermoelectric, optical thin-film coating, and thermodynamic properties of K2Ag(Ga/In)Br6 (lead-free halide double perovskites, HDPs) was performed using first-principles calculations. The optimized structural parameters are in good agreement with the available data. Furthermore, Goldsmith's tolerance factor indicates an ideal value for both double perovskites, ensuring the structural stability of the cubic perovskites, and the elasticity parameters were analyzed to ensure the mechanical stability of the cubic phase. Direct and reduced band gaps of 0.4524 eV and 1.064 eV with semiconductor behavior are found for K2AgGaBr6 and K2AgInBr6, respectively, through adoption of the modified Becke–Johnson potential scheme. The absorption coefficient, refractive index, and dielectric function, as some of the optical properties, in addition to the optical thin-film properties, are well discussed, and the values suggest that these materials are promising candidates for different devices, such as optoelectronic and photovoltaic energy devices. In terms of the thermodynamics, the HDPs display favorable characteristics across various temperature and pressure ranges. Additionally, we assessed the thermoelectric properties, considering the power factor, Seebeck coefficient, thermal and electronic conductivities, and figure of merit. The current predictions suggest that these lead-free halide double perovskites have strong potential for application in thermoelectricity and photovoltaics.

Development of generalized photovoltaic model using ISIS-PROTEUS

Photovoltaic (PV) energy is a form of renewable energy that generates electricity from sunlight. PV systems consist of solar cells, which convert sunlight into electricity using a process known as the photovoltaic effect. Modeling and simulating PV systems involves using mathematical and computational models to predict the behavior and performance of PV systems under various conditions. This can include modeling the electrical characteristics of solar cells, as well as the interactions between multiple cells in a PV module or system. Following this sense, we present in this work a novel implementation of a generalized PV model using ISIS Proteus software. Proteus is layout software for electronic circuit simulation, schematic capture and PCB design. Some studies have indeed taken this context to model the PV modules either by using a Proteus Spice model of the photovoltaic panel without including the effect of climatic conditions variation, or by using pure mathematical relations that describe all physical and environmental parameters which will lead to a static behavior. The developed model in this paper as it is generalized, can be typically used as a PV cell, module even a generator for a complete simulation of a PV system. PV cell, which is the elementary component of PV system, is modeled using the single diode equivalent circuit (SDM) also known as five-parameter model and its behavior is simulated in details. The most advantage in our study is the fact that the PV output can be obtained wherever what solar radiation and ambient temperature where PV module is operating. Our model gives also the possibility to simulate a dynamic behavior under any climatic conditions. The accuracy between obtained results of simulation and the experimental data confirm the reliability and the high performance of the developed model.

Explicit representation of S-shaped and standard V–I curve of illuminated solar cell

A generalized explicit model is proposed in this study to model the S-shaped and standard voltage-current characteristics (V–I) of illuminated solar cells. Even though the voltage-current characteristics of a typical solar cell follow a single exponential model (single diode model), there is evidence of S-shaped voltage-current characteristics that cannot be captured by the existing standard analytical models. The proposed explicit analytic representation is comparatively simple and produces satisfactory results in depicting the voltage-current curve for a wide variety of solar cells, including those with S-shaped characteristics. The methodology for determining the empirical parameters of the proposed model is also described, including an easy estimation of maximum power point voltage using model parameters.

Enhancing Pb-free inorganic perovskite solar cell using carbon as metal back contact and molybdenum trioxide as hole transport layer

Inorganic Pb-free perovskite solar cells have appeared in recent years as a promising and environmentally friendly technology in photovoltaics. In this study, we conducted a comprehensive simulation investigation using SCAPS-1D software to optimize Pb-free inorganic perovskite solar cells, focusing specifically on the use of RbGeI3 as the absorber material in the FTO/TiO2/RbGeI3/MoO3/C device architecture. The carbon back contact in this configuration stands out for its cost-effectiveness and durability. Our research focused on the influence of various critical parameters, including the thickness of the absorber, electron affinity of ETL and HTL, series, and shunt resistances, back-contact material work functions, and operating temperatures. This achieved a PCE of 29.47 %, FF of 78.22 %, VOC of 1.111 V and JSC of 33.91 mA/cm2. The results indicate that perovskite solar cells using RbGeI3 as an absorber material exhibit improved performance and good thermal stability, underlining the great potential of this material. In addition, the eco-friendly characteristics of these Pb-free inorganic perovskite solar cells hold great promise for advancing the field of clean energy conversion technologies, marking an important step towards sustainable and efficient energy solutions.

Improving photovoltaic cell parameter calculations through a puffer fish inspired optimization technique

The precise estimation of solar PV cell parameters has become increasingly important as solar energy deployment expands. Due to the intricate and nonlinear characteristics of solar PV cells, meta-heuristic algorithms show greater promise than traditional ones for parameter estimation. This study utilizes the Puffer Fish (PF) meta-heuristic optimization method, inspired by male puffer fish's circular structures, to estimate parameters of a modified four-diode PV cell. The PF algorithm's performance is assessed against ten benchmark test functions, with results presented as mean and standard deviation for validation. Comparative analysis with Particle Swarm Optimization (PSO), Grey Wolf Optimization (GWO), Rat Search Algorithm (RAT), Heap Based Optimizer (HBO), and Cuckoo Search (CS) algorithms highlights PF's superior performance, achieving optimal solutions with minimal error of 7.8947E-08. Statistical tests, including Friedman Ranking (1st) and Wilcoxon's rank sum (3.8108E-07), confirm PF's superiority. The circular structures of male puffer fish serve as an effective model for optimization algorithms, enhancing parameter estimation. Benchmark tests and statistical analysis consistently underscore PF's superiority over other meta-heuristic algorithms. Future research should explore PF's potential applications in solar energy and beyond.

Characteristics of thin film solar cells as the future energy

Characteristics of thin film solar cells as the future energy

Spin coating on a budget: A 3D-Printed all-mechanical alternative for cost-effective thin-film deposition

Spin coating stands out as the most employed thin-film deposition technique across a variety of scientific fields. Particularly in the past two decades, spin coaters have become increasingly popular due to the emergence of solution-processed semiconductors such as quantum dots and perovskites. However, acquiring commercial spin coaters from reputable suppliers remains a significant financial burden for many laboratories, particularly for smaller research or educational facilities. Prompted by the simple mechanical principles of the device, in this work, we present a 3D-printed analogue that can be printed and assembled in under 10 h and costs less than 5 euros per device. The operating principle is fully mechanical since the rotating motion is induced by gas flow. It does not require any additional components such as DC motors, motor drivers, circuitry or software and thus it can be fully operational off the grid. Additionally, the gas flow generates a purging effect that was found to be rather advantageous for film formation. To prove the effectiveness of this device, we have employed it to fabricate planar thin-film antimony sulfide (Sb2S3) solar cells. The optoelectronic characteristics of solar cells revealed noteworthy improvements, particularly in terms of repeatability, when compared to those fabricated with a commercial spin coater.

A test of meta-heuristic algorithms for parameter extraction of next-generation solar cells with S-shaped current–voltage curves

Identifying parameters of photovoltaic (PV) models based on measured current–voltage (IV) characteristic curves is critical for simulating, evaluating, and controlling PV systems. IV characteristics of the latest-generation solar cells (SCs) often display an S-shaped deformation. In this paper, we explore the potential of meta-heuristic algorithms to address the parameter estimation problems associated with PV cells that exhibit S-shaped IV characteristics. This estimation is performed within the framework of the opposed two-diode model. We implemented a total of 14 algorithms from various classes to extract the SC parameters from synthetic IV curves, which were generated using a range of parameter values. The results were compared by using nonparametric statistical methods. These methods include the Wilcoxon signed-rank test for pairwise comparisons, and the Friedman, Friedman Aligned, and Quade tests for multiple comparisons. Comprehensive results and analyses show that the STLBO (Simplified teaching–learning based optimization algorithm) and ADELI (Adaptive differential evolution with the Lagrange interpolation argument) algorithms demonstrate highly competitive performance in terms of accuracy and reliability. This paper underscores the efficacy of advanced meta-heuristic algorithms in solving complex non-linear optimization problems in the domain of photovoltaic research, particularly concerning the unique challenges posed by S-shaped IV characteristics of new-generation solar cells.