Solar Cells Research Articles

A Survey Paper on Plastic Solar Cell Technology

The demand of energy is increasing day by day so non-conventional source of energy has to be used. Sun is the nonconventional source of energy. Conventional solar panels convert solar energy into electrical energy. A plastic solar cell is the type of photovoltaic that makes use of organic electronics dealing with conductive organic polymers or small molecules for light absorption and charge transport to produce electricity from sunlight by the photovoltaic effect. Polymers Provide the Advantage of Solution Processing at Room Temperature, which is Less Expensive and Enables One to Use Plastics. Therefore, If Silicon Is Replaced with Polymer Nanowires, The Solar Cell Would Be Much Lighter and Ultimately Less Costly. These Solar Cells are Thin, Several Microns in Diameter, and Scavenge All the Rays from the Sun's Radiation. Plastic Solar Cell Technology is Based on Conjugated Polymers and Molecules. Polymer Solar Cells have Generated Considerable Interest Since it Provides Environmentally Friendly, Flexible, Lightweight, Low Cost, Possibility of High-Efficiency Solar Cells in the Last Couple of Decades. Plastic Solar Cells are More Efficient and Viable in Usage. This dissertation focuses on the development and optimization of plastic solar cell technology, in particular this potential towards flexible, lightweight, and cost-effective alternative sources to traditional silicon-based solar cells. The focus of the present research work is to find optimum organic materials for higher efficiency and stability in plastic solar cells, varying from conjugated polymers to small organic molecules. Some of the main goals are improving the charge transport mechanisms and optimizing the architecture of devices through state-of-the-art techniques of fabrication, like roll-to-roll printing and layer-by-layer deposition. The other key aspect is that the project assesses the environmental aspects and lifecycle of plastic solar cells to ensure an environmentally friendly production process. Huge preliminary results were achieved at high power conversion efficiencies and durability has been greatly improved, targeting very wide spread application from portable electronics up to building-integrated photovoltaics. Therefore, the discovery of plastic solar cells might be a major step for applicable solutions in renewable energy and towards overcoming the world's increasing energy challenges.

Warranty-driven reliability analysis: a stochastic model for continuous solar power supply system with two photovoltaic cells and an inverter

Warranty-driven reliability analysis: a stochastic model for continuous solar power supply system with two photovoltaic cells and an inverter

Controllable Heavy n–type Behaviours in Inverted Perovskite Solar Cells with Non‐Conjugated Passivants

AbstractInterfacial issues between the perovskite film and electron transport layer greatly limit the efficiency and stability of inverted (p‐i‐n) perovskite solar cells (PSCs). Despite organic ammonium passivants have been widely established as interfacial layers, they failed to improve electron extraction. Here, we reported that the heavy n‐type characteristics in a low band gap perovskite film could be modulated by incorporating non‐conjugated ammonium passivants with strong electron‐withdrawing abilities. This resulted in a significant enhancement of electron extraction in the heavily n‐type doped perovskite. The passivant‐treated PSCs exhibited a power conversion efficiency of 25.74 % with an excellent fill factor of 85.4 % and a high open‐circuit voltage of 1.166 V, which are significantly higher than that of the control device. The unencapsulated devices maintained 88 % of their initial PCEs after 1,200 hours at 85 °C.

Effect of Perovskite Active Layer Thickness on the Performance of Photovoltaic Cells and Radiation Detectors

Effect of Perovskite Active Layer Thickness on the Performance of Photovoltaic Cells and Radiation Detectors

Improving Solar Cell Efficiency of Silicon and Silicon Tandem Structure by Using Surface Modification

Silicon heterojunction (SHJ) solar cells face challenges in maximizing energy capture due to limitations in light collection and surface passivation. To address this, the use of SHJ tandem solar cells in a back‐to‐back configuration is explored, allowing illumination from both sides to enhance light absorption and energy generation. This study aims to improve the stability and efficiency of these cells through Al2O3 and Nafion surface treatments. Al2O3 is deposited to enhance bifacial light collection, while Nafion is applied for surface passivation to increase the fill factor (FF). The method involves adding 0.1–0.6 units of incident light to the rear of the cells to evaluate the effects of these treatments. The results show a 2.06% increase in efficiency with Al2O3 and a 1.72% improvement with Nafion under standard illumination conditions. The optimized tandem SHJ with Al2O3 and Nafion achieves a Jsc of 62.01 mA cm−2, Voc of 650.63 mV, FF of 76.49%, and an efficiency of 30.86%. These findings demonstrate the significant potential of these surface treatments to enhance the overall performance of bifacial back‐to‐back tandem SHJ solar cells.

UV‐Induced Degradation of Industrial PERC, TOPCon, and HJT Solar Cells: The Next Big Reliability Challenge?

With the surge of UV‐transparent module encapsulants in the photovoltaic industry aiming to boost quantum efficiency, modern silicon solar cells must now inherently withstand UV exposure. UV‐induced degradation (UVID) of nonencapsulated laboratory and industrial solar cells from several manufacturers is investigated. Passivated emitter rear contact (PERC), tunnel oxide passivating contact (TOPCon), and silicon heterojunction (HJT) cells can suffer from severe implied voltage degradation (>20 mV) after UV exposure relating to 3.8 years of module installation in the Negev desert. Front UV‐exposure causes more performance loss than an equal rear dose. This is connected to a higher UV transmission of the cell layers outside the bulk, indicating the photons need to reach the silicon surface to induce damage. Current–voltage measurements of the TOPCon groups most sensitive to UV degradation show more than 7%rel efficiency loss with the Voc as the main contributor. For two TOPCon groups, dark storage for 14 days after UV exposure causes an additional voltage drop on a similar scale as the UV damage itself, impeding straightforward reliability testing. UVID appears to be a complex process general to all dominant cell architectures with the potential to diminish efforts in efficiency optimization within only a few years of field employment.

Modulating phase segregation during spin-casting of fullerene-based polymer solar-cell thin films upon minor addition of a high-boiling co-solvent

The impact of additives on the nanoscale structures of spin-cast polymer composite films, particularly in polymer solar cells, is a topic of significant interest. This study focuses on the blend film comprising poly(thieno[3,4-b]thiophene-alt-benzodithiophene) (PTB7) and [6,6]-phenyl-C71-butyric acid methyl ester (PC71BM), exploring how additives like 1,8-diiodooctane (DIO) influence the film structures spin-cast from chlorobenzene solution. Combined results of specular X-ray and neutron reflectivity, grazing-incidence small- and wide-angle X-ray scattering (GISAXS and GIWAXS), and X-ray photoelectron spectroscopy indicate that DIO could significantly enhance the dispersion of PC71BM and reduce composition inhomogeneity in the film. Time-resolved GISAXS–GIWAXS with 100 ms resolution further captures a rapid spinodal decomposition of the mixture within 1 s in the constant-evaporation stage of spin-casting. Further combined with parallel analysis of time-resolved UV–Vis reflectance, these findings reveal that DIO mitigates the spinodal decomposition process by accelerating solvent evaporation, which, in turn, decelerates phase segregation, leading to a nucleation-driven process. These observations provide mechanistic insights into the role of additives in controlling the nanostructural evolution of spin-cast films by altering the kinetics of solvent evaporation and phase separation during the spin-coating process.

All-In-One Additive Enabled Efficient and Stable Narrow-Bandgap Perovskites for Monolithic All-Perovskite Tandem Solar Cells.

Hybrid tin-lead (Sn-Pb) perovskites have garnered increasing attention due to their crucial role in all-perovskite tandem cells for surpassing the efficiency limit of single-junction solar cells. However, the easy oxidation of Sn2+ and fast crystallization of Sn-based perovskite present significant challenges for achieving high-quality hybrid Sn-Pb perovskite films, thereby limiting the device's performance and stability. Herein, an all-in-one additive, 2-amino-3-mercaptopropanoic acid hydrochloride (AMPH) is proposed, which can function as a reducing agent to suppress the formation of Sn4+ throughout the film preparation. Furthermore, the strong binding between AMPH and Sn-based precursor significantly slows down the crystallization process, resulting in a high-quality film with enhanced crystallinity. The remaining AMPH and its oxidation products within the film contribute to improves oxidation resistance and a substantial reduction in defect density, specifically Sn vacancies. Benefiting from the multifunctionalities of AMPH, a power conversion efficiency (PCE) of 23.07% is achieved for single-junction narrow-bandgap perovskite solar cells. The best-performing monolithic all-perovskite tandem cell also exhibits a PCE of 28.73% (certified 27.83%), which is among the highest efficiency reported yet. The tandem devices can also retain over 85% of their initial efficiencies after 500 hours of continuous operation at the maximum power point under one-sun illumination.

Apparent Intensity Dependence of Shunts in PV Modules Revision of the Shunt Parameterization in the De Soto Model and PVsyst

ABSTRACTIt is common practice in PV system simulation to use the De Soto model, which describes how to use the 1‐diode equivalent circuit model for modules. De Soto's model scales the shunt with irradiance, making it disappear toward zero W/m2. Also, the commercial software PVsyst uses a parameterization that reduces the shunt effect when the irradiance goes down. However, the solar cells that make up a module typically do not have an illumination‐dependent shunt. We therefore investigate the origin of the intensity‐dependent apparent shunt in modules. We show that this apparent shunt (derived from the slope of the quasi‐linear region from ISC onwards) is a misinterpretation for module I‐V curves and has little to do with a shunt conductance, although this slope method serves well for determining the shunt conductance of individual cells. Instead, the module I‐V curve slope of the quasi‐linear region from ISC onwards is strongly influenced by even small ISC mismatches between the cells. Such mismatch can occur from small illumination inhomogeneity even for A+ solar simulators in the laboratory, or from cell production variation. Abandoning the practice of using the I‐V curve slope to determine the shunt value for equivalent circuit models of modules (and the corresponding shunt scaling in the De Soto model or PVsyst) contributes to physically more meaningful I‐V curve parameterizations and bears the opportunity for further improved accuracy of PV system energy yield prediction.

Stabilizing Wide‐Bandgap Perovskite with Nanoscale Inorganic Halide Barriers for Next‐Generation Tandem Technology

AbstractWide‐bandgap (WBG) perovskite solar cells (PSCs) play a crucial role in advancing perovskite‐based tandem solar cells. In WBG perovskite films, grain boundary (GB) defects are the main contributors to open‐circuit voltage (VOC) deficits and performance degradation. This report presents an effective strategy for passivating GBs by incorporating an inorganic protective layer and reducing the density of GBs in perovskite films. This is achieved by integrating potassium thiocyanate (KSCN) into I‐Br mixed halide WBG perovskites. It is reported for the first time that the incorporation of KSCN creates band‐shaped barriers along the GBs. In addition, KSCN enlarges the grains of perovskite film. Elemental and structural analyses reveal that these barriers are composed of potassium lead halide. Incorporating KSCN significantly enhances the fill factor and VOC of WBG single‐junction PSCs by reducing trap density. This results in high power conversion efficiencies of 19.22% (bandgap of 1.82 eV), 20.45% (1.78 eV), and 21.54% (1.70 eV) with a C60/bathocuproine electron transport layer, and 18.51% (1.82 eV) with a C60/SnO2. Furthermore, both operational and shelf stabilities are significantly improved due to reduced light‐induced halide segregation. By using inorganic‐halide‐passivated WBG sub‐cells, a monolithic all‐perovskite tandem solar cell with an efficiency of 27.04% is demonstrated.

Is Shunt Quenching Relevant to Minimize Shunt Losses in Perovskite–Silicon Tandem Solar Cells?

One challenge in thin‐film based solar cells, including perovskite‐silicon tandem cells, is the defect‐free deposition of the thin‐film layers. Such defects can result in high local parasitic current losses, that is, local shunt spots. Depending on the nature of the defects, their geometrical distribution can either be microscopic, for example, induced by texture morphology, or macroscopic, for example, induced by particles during processing. Instead of avoiding the defects themselves, so‐called shunt‐quenching methods have been proposed to mitigate the associated efficiency loss. This work investigates the following recently suggested methods: 1) a deliberate current mismatch; and 2) engineering the resistive properties of the intermediate layers between the subcells to electrically isolate the shunt. A comprehensive 3D device simulation study is presented to quantitatively analyze the (in)effectiveness of these methods. It is found that shunt‐quenching by a deliberate current mismatch can only play a minor role in the overall optimization of the current match point. Engineering the resistive properties of the intermediate layers must be generally considered ineffective. It only works for the rather specific case of strong and macroscopically distributed shunts with little cell‐to‐cell variation and only if some further requirements of the cell design are met.

Perovskite Solar Cell Stability Analysis Using Entropy‐Based Support Vector Machines Learning

ABSTRACTLead halide perovskites have demonstrated significant potential for photovoltaic (PV) applications over the past 10 years. Perovskite solar cells (PSCs) stability, however, continues to limit their commercialization, and the inability to compare previous stability data to assess possible directions for increasing device stability is caused by a lack of effectively established unified stability testing and disseminating standards. In this article, we suggest applying machine learning (ML) to improve the thermal, chemical, and structural stability of PSCs. Data normalization and data augmentation are common preprocessing steps that are where the process starts. Then, using the Modified Grasshopper Optimisation Algorithm (MGO), feature selection techniques are used to remove unnecessary or irrelevant features. Finally, there is a novel machine learning technique that uses support vector machines (ESVM) that are based on entropy to forecast the stability classification of stable/unstable. The proposed reaches an accuracy of 0.99% far better than the proposed methods.

Application of PACz-Based Self-Assembled Monolayer Materials in Efficient Perovskite Solar Cells.

Due to the advantages of low interface resistance, high work function, and high stability, PACz family materials have developed rapidly in p-i-n structure perovskite solar cells (PSCs) in recent years. Numerous studies have shown that PSCs prepared on the basis of PACz family materials or their derivatives as hole transport layers (HTLs) generally exhibit superior performance compared to PSCs prepared on the basis of organic HTL PTAA and inorganic HTL NiOx, especially in terms of stability, demonstrating unparalleled charm. Since the application of PACz-like molecule V1036 as a HTL in PSCs in 2018, research reports on high-performance PSCs based on the PACz family HTL have been widely disseminated. Currently, PSCs based on the PACz HTL exhibit a world record value of 26.7% power conversion efficiency (PCE), breaking the long-standing world record held by n-i-p-structured PSCs, indicating its great potential for application in PSCs. The main problem with using PACz as a HTL is that it exhibits poor wettability toward perovskite precursor solutions, is sensitive to the thickness of the HTL and the roughness of the substrate, has poor thermal stability, and lacks preparation methods, making it difficult to achieve large-area device fabrication. This review summarizes the outstanding achievements of PACz to date, describes the mechanism and unique properties of PACz in PSCs, and looks forward to the future development prospects of PACz.

Crystallization Control of Blade‐Coated Wide Bandgap FACs‐Based Perovskite

AbstractTransforming perovskite solar cells into commercial production requires advanced scalable deposition technology. However, the deposition of high‐quality perovskite thin films using the blade coating method presents challenges, especially in controlling the nucleation and crystallization of perovskite. In this work, an effective approach is proposed for controlling nucleation and crystallization by simultaneously incorporating two kinds of ionic liquid, namely 1H‐imidazole acetate (IMAc), and 1‐buty‐3‐methylimidazolium tetrafluoroborate (BMIMBF4), into the precursor solution. This innovative strategy initiates π–π interactions between IM and BMIM cations, thereby enhancing the interaction between cations and the Pb‐I framework. The competitive mechanism of interaction with Pb‐I framework effectively suppresses the formation of unfavorable mesophase, thereby enabling a single crystallization pathway from NMP + PbI2 to α‐perovskite. Consequently, this method effectively reduces defects and enhances the crystal quality of α‐perovskite film. Based on this strategy, the power conversion efficiency of the p‐i‐n wide bandgap perovskite device prepared by the blade coating method, is increased to 21.31%, representing one of the highest efficiencies achieved with this technology for 1.68 eV bandgap FACs‐based perovskites. Thus, this approach emerges as a feasible breakthrough strategy that may unleash the full potential of perovskite solar cells.

Stable Surface Contact with Tailored Alkylamine Pyridine Derivatives for High-Performance Inverted Perovskite Solar Cells.

Formamidinium-cesium lead triiodide (FA1-xCsxPbI3) perovskite holds great promise for perovskite solar cells (PSCs) with both high efficiency and stability. However, the defective perovskite surfaces induced by defects and residual tensile strain largely limit the photovoltaic performance of the corresponding devices. Here, the passivation capability of alkylamine-modified pyridine derivatives for the surface defects of FA1-xCsxPbI3 perovskite is systematically studied. Among the studied surface passivators, 3-(2-aminoethyl)pyridine (3-PyEA) with the suitable size is demonstrated to be the most effective in reducing surface iodine impurities and defects (VI and I2) through its strong coordination with Npyridine. Additionally, the tail amino group (─NH2) from 3-PyEA can react with FA+ cations to reduce the surface roughness of perovskite films, and the reaction products can also passivate FA vacancies (VFA), and further strengthen their binding interaction to perovskite surfaces. These merits lead to suppressed nonradiative recombination loss, the release of residual tensile stress for the perovskite films, and a favorable energy-level alignment at the perovskite/[6,6]-phenyl-C61-butyric acid methyl ester interface. Consequently, the resulting inverted FA1-xCsxPbI3 PSCs obtain an impressive power conversion efficiency (PCE) of 25.65% (certified 25.45%, certified steady-state efficiency 25.06%), along with retaining 96.5% of the initial PCE after 1800 h of 1-sun operation at 55 °C in air.

Nanostructured AlxIn1−xPySbzAs1−y–z semiconductor alloy as a competent material for optoelectronic and solar cell applications

Nanostructured AlxIn1−xPySbzAs1−y–z semiconductor alloy as a competent material for optoelectronic and solar cell applications

Triphenylamine-Based Y-Shaped Self-Assembled Monolayers for Efficient Tin Perovskite Solar Cells.

Triphenylamine-based Y-shaped organic sensitizers, specifically TPA-MN (1), TPA-CA (2), TPAT-MN (3), and TPAT-CA (4), are synthesized and utilized as p-type self-assembled monolayers (SAMs) for tin-based perovskite solar cells (TPSCs). These SAMs are developed using low-cost starting materials, primarily from triphenylamine (TPA) components. An extensive analysis is conducted to examine the crystalline, morphological, thermal, optical, electrochemical, and optoelectronic characteristics of SAMs 1-4, and the results are compared. A two-step method is employed to successfully develop tin perovskite layers on all four SAM surfaces. The resulting devices demonstrates PCE in the following order: TPAT-CA (8.1%) > TPAT-MN (6.1%) > TPA-MN (5.0%) > TPA-CA (4.2%). The TPAT-CA molecule, which contains a thiophene spacer, performed better than the other three SAMs in terms of rapid hole extraction rate, high hole mobility, and retarded charge recombination. Consequently, SAM TPAT-CA exhibited the highest device performance with excellent stability over time, retaining ≈90% from the beginning values after storage for 3000 h. The innovative Y-shaped SAMs describe in this study, characterized by their simple and efficient design, have the potential to contribute significantly to the advancement of perovskite photovoltaics, particularly in the development of cost-effective TPSC technology.

Visualization of Anion Vacancy Defect Annihilation in CZTSe Solar Cells by Hydrogen-Assisted Selenization with In Operando X-ray Nanoprobe Studies.

The traditional sulfur selenization process in Cu2ZnSn(S,Se)4 (CZTSSe) solar cell fabrication often results in the creation of localized anion vacancies (VS and VSe). These vacancies are considered harmful defects as they can trap carriers generated by light, leading to reduced solar cell efficiency. Moreover, concrete evidence has been lacking on the extent of the impact caused by these anion vacancies. Our research introduces a novel approach: the hydrogen-assisted selenization (HAS) process, specifically designed to minimize localized anion vacancies in Cu2ZnSnSe4 (CZTSe) solar cells. Our investigation, utilizing current-voltage (I-V) and admittance spectroscopy measurements, provides clear insights. We observed notable improvements in carrier collection efficiency and a discernible reduction in defect states. Furthermore, there was a significant decrease in the activation energy required within the solar cell device, dropping from 184 to 145 meV. To delve deeper into the structural and compositional aspects, we employed synchrotron-based X-ray nanoprobes. Through nanoscale X-ray fluorescence and hard X-ray beam-induced current measurements, we can directly observe and document the relationship between the local compositional distribution and photocurrent activity in operando. These comprehensive results furnish strong evidence that mitigating anion vacancies in the CZTSe layer can substantially improve the power conversion efficiency of the CZTSe solar cells. This advancement not only sheds light on the critical role of anion vacancies in solar cell performance but also underscores the effectiveness of the HAS process in enhancing overall device efficiency.

Nanomaterials for Energy Conversion

Nanomaterials have emerged as a cornerstone in advancing energy conversion technologies, offering unparalleled potential for improving efficiency and sustainability. Their unique properties—such as high surface area, tunable electronic structure, and quantum effects—enable superior performance in applications like solar cells, fuel cells, thermoelectric devices, and batteries. By manipulating nanoscale architectures, researchers can enhance energy harvesting, storage, and conversion processes. This study explores the role of nanomaterials in energy conversion, focusing on their design, synthesis, and application in cutting-edge technologies. The integration of nanomaterials with advanced energy systems has shown significant potential to address challenges such as limited energy resources and environmental concerns. Special emphasis is placed on nanostructured semiconductors, quantum dots, and graphene-based materials for their contributions to photovoltaic and catalytic processes. Despite their advantages, challenges remain, including scalability, stability, and cost-efficiency. This research aims to provide a comprehensive overview of recent advancements, evaluate existing challenges, and highlight future directions for nanomaterials in energy conversion, ultimately contributing to a sustainable energy future.

Synthesis and Mechanistic Study of Naphthalimide Derivative Formation via Cu-Mediated Ullmann-Type Reactions.

Cu-mediated Ullmann-type coupling reactions are fundamental to organic synthesis, garnering significant academic and industrial interest since their inception. Optimizing reaction parameters, particularly temperature control, is crucial for maximizing efficiency while maintaining high yields. Bidentate ligands, such as amino acids, have demonstrated potential in facilitating these reactions at lower temperatures (<100 °C). This study explores the Cu-catalyzed Ullmann-type coupling of naphthalimide derivatives with amino acid substitutions. Naphthalimide dyes, known for their diverse applications in bioimaging, solar cells, medicine, and sensors, were selected for their potent anticancer properties. The synthesized compounds were characterized by using 1H NMR, ESI-MS, and melting point analyses. Compounds with significant steric hindrance exhibited lower yields, leading to the development of a novel catalytic system employing l-carnosine as a bidentate ligand, which significantly improved yields. Mechanistic insights, derived from density functional theory calculations, identified "L-complex 3" as the most stable and reactive intermediate during oxidative addition to aryl halides. The oxidative addition transition state "OX1-TS" was found to be the most favorable, with a relatively low energy barrier of 6.13 kcal/mol, suggesting that this step, despite being the rate-limiting stage, is energetically accessible. In contrast, reductive elimination was facilitated by a Cu(III) penta-coordinated intermediate, with a barrier of just 8.34 kcal/mol, making it a more straightforward process. Theoretical findings aligned closely with experimental data, reinforcing the oxidative addition/reductive elimination pathway as the operative mechanism for this reaction.