Perovskite Solar Modules Research Articles

Chemically‐Modified 2D Covalent Organic Framework as an HTL Dopant for High‐Performance, Stable, and Sustainable Perovskite Solar Cells and Modules

AbstractDespite significant advances in perovskite solar cells (PeSCs), the operational instability and susceptibility to Pb leakage of PeSCs severely limit their widespread application. To address these issues, this study investigates the effect of doping the Spiro‐OMeTAD hole‐transporting layer (HTL) with a chemically‐modified 2D conjugated covalent organic framework (Tp‐Azo‐COF) on the photovoltaic performance and stability of PeSCs. Enriched with abundant carbonyl (C═O) groups and azo (N═N) nodes, Tp‐Azo‐COF has excellent chelation and adsorption capabilities, and experimental results confirm that Tp‐Azo‐COF effectively decreases Pb leakage and Li‐ion migration, improving the environmental safety and operational stability of PeSCs. The optimized PeSCs (0.12 cm2) exhibit an efficiency of 24.25%, a new benchmark for COF‐modified devices, and maintain robust performance in large‐area modules (18 cm2) with an efficiency of 21.96%. Under accelerated aging tests, including continuous light irradiation at maximum power point tracking for 980 h, the module demonstrated exceptional durability, with near‐100% efficiency retention. The COF doping strategy developed in this study significantly enhances operational stability and minimizes Pb leakage in PeSCs, paving the way for the sustainable, large‐scale deployment of perovskite photovoltaics.

Tailored Supramolecular Interactions in Host–Guest Complexation for Efficient and Stable Perovskite Solar Cells and Modules

AbstractHost‐guest complexation offers a promising approach for mitigating surface defects in perovskite solar cells (PSCs). Crown ethers are the most widely used macrocyclic hosts for complexing perovskite surfaces, yet their supramolecular interactions and functional implications require further understanding. Here we show that the dipole moment of crown ethers serves as an indicator of supramolecular interactions with both perovskites and precursor salts. A larger dipole moment, achieved through the substitution of heteroatoms, correlates with enhanced coordination with lead cations. Perovskite films incorporating aza‐crown ethers as additives exhibited improved morphology, reduced defect densities, and better energy‐level alignment compared to those using native crown ethers. We report power‐conversion efficiencies (PCEs) exceeding 25 % for PSCs, which show enhanced long‐term stability, and a record PCE of 21.5 % for host–guest complexation‐based perovskite solar modules with an active area of 14.0 cm2.

Tailored Supramolecular Interactions in Host-Guest Complexation for Efficient and Stable Perovskite Solar Cells and Modules.

Host-guest complexation offers a promising approach for mitigating surface defects in perovskite solar cells (PSCs). Crown ethers are the most widely used macrocyclic hosts for complexing perovskite surfaces, yet their supramolecular interactions and functional implications require further understanding. Here we show that the dipole moment of crown ethers serves as an indicator of supramolecular interactions with both perovskites and precursor salts. A larger dipole moment, achieved through the substitution of heteroatoms, correlates with enhanced coordination with lead cations. Perovskite films incorporating aza-crown ethers as additives exhibited improved morphology, reduced defect densities, and better energy-level alignment compared to those using native crown ethers. We report power-conversion efficiencies (PCEs) exceeding 25 % for PSCs, which show enhanced long-term stability, and a record PCE of 21.5 % for host-guest complexation-based perovskite solar modules with an active area of 14.0 cm2.

Bilayer interface engineering through 2D/3D perovskite and surface dipole for inverted perovskite solar modules

The persistency of passivation and scalable uniformity are vital issues that limit the improvement of performance and stability of large-area perovskite solar modules (PSMs). Here, we design a bilayer interface engineering strategy that takes advantage of the stability and passivation ability of low-dimensional perovskite and the dipole layer. Introducing phenethylammonium iodide (PEAI) can form 2D/3D heterojunctions on the perovskite surface and effectively passivate defects of perovskite film. Interestingly, the upper piperazinium iodide (PI) layer can still form surface dipoles on the 2D/3D perovskite surface to optimize energy-level alignment. Moreover, the bilayer interface engineering enables large-area perovskite films with uniform surface morphology, lower trap-state density and stability against environmental stress factors. The final devices achieved a small-area PCE of 25.20% and a large-area (1 ​cm2) PCE of 23.96%. A perovskite mini-module (5 ​× ​5 ​cm2 with an active area of 14.28 ​cm2) could also be fabricated to achieve a PCE of 23.19%, ranking it among the highest for inverted PSMs. Additionally, the device could retain over 93% of its initial efficiency after MPP tracking at 45 ​°C for 1280 ​h. This study successfully demonstrates a bilayer interface engineering with respective functions, offering valuable insights for producing efficient and stable large-area PSCs.

Unified Crystal Phase Control with MACl for Inducing Single-Crystal-Like Perovskite Thin Films in High-Pressure Fusion Toward High Efficiency Perovskite Solar Cell Modules.

Perovskite solar cells, recognized for their high photovoltaic conversion efficiency (PCE), cost-effectiveness, and simple fabrication, face challenges in PCE improvement due to structural defects in polycrystalline films. This study introduces a novel fabrication method for perovskite films using methylammonium chloride (MACl) to align grain orientation uniformly, followed by a high-pressure process to merge these grains into a texture resembling single-crystal perovskite. Employing advanced visual fluorescence microscopy, charge dynamics in these films are analyzed, uncovering the significant impact of grain boundaries on photo-generated charge transport within perovskite crystals. A key discovery is that optimal charge transport efficiency and speed occur in grain centers when the grain size exceeds 10µm, challenging the traditional view that efficiency peaks when grain size surpasses film thickness to form a monolayer. Additionally, the presence of large-sized grains enhances ion activation energy, reducing ion migration under light and improving resistance to photo-induced degradation. In application, a perovskite solar cell module with large grains achieve a PCE of 22.45%, maintaining performance with no significant degradation under continuous white LED light at 100 mA cm-2 for over 1000h. This study offers a new approach to perovskite film fabrication and insights into optimizing perovskite solar cell modules.

Low-Cost, Scalable Fabrication of Multi-Dimensional Perovskite Solar Cells and Modules Assisted by Mechanical Scribing.

The performance and scalability of perovskite solar cells (PSCs) based on 3D formamidinium lead triiodide (FAPbI3) absorber are often hindered by defects at the surface and grain boundaries of the perovskite. To address this, the study demonstrates the use of pyrrolidinium iodide for the in situ formation of an energetically aligned 1D pyrrolidinium lead triiodide (PyPbI3) capping layer over the 3D FAbI3 perovskite. The thermodynamically stable PyPbI3 perovskitoids, formed through cation exchange reactions, effectively reduce surface and grain boundary defects in the FAPbI3 perovskite. In addition to improved phase stability, the resulting 1D/3D perovskite film forms a cascade energy band alignment with the other functional layers in PSCs, enabling a barrier-free interfacial charge transport. With a maximum power conversion efficiency (PCE) of ≈23.1% and ≈20.7% at active areas of 0.09 and 1.05 cm2, respectively, the 1D/3D PSCs demonstrate excellent performance and scalability. Leveraging this improved scalability, the study has successfully developed a mechanically-scribed 1D/3D perovskite mini-module with an unprecedentedly high PCE of ≈20.6% and a total power output of ≈270mW at an active area of ≈13.0 cm2. The 1D/3D multi-dimensional perovskite film developed herein holds great promise for producing low-cost, high-performance perovskite photovoltaics at both the cell and module levels.

Electrodeposited mesoporous TiO2 thin films and their application as the scalable electron transport layer for perovskite solar modules

In this study, we present the utilization of electrodeposited TiO2 mesoporous film (ED-MS-TiO2) as the electron transport layer (ETL) for perovskite solar cells, especially marking the first report of its application in perovskite solar modules. In the first part of this paper, we refine the electrodeposition process to enhance the porosity of the ED-MS-TiO2 thin film by elevating the ED temperature from room temperature to a mild 60 °C. Notably, the ED-MS-TiO2 ETL fabricated at 60 °C demonstrates comparable charge extraction capability and conversion efficiency to the benchmark ETL produced via the widely adopted spin-coating technique, achieving a remarkable 20.5 %. Furthermore, we demonstrate the immense superiority of the ED process in achieving uniformity in the preparation of large-area ETLs. Our current findings reveal that ED-MS-TiO2 exhibits exceptional uniformity control, with a thickness distribution of 122.69 ± 8.39 nm on a 100 cm² substrate, while its spin-coated counterpart exhibits poor thickness control, measuring 135.72 ± 50.72 nm. Moreover, perovskite solar modules (5 cm × 5 cm) employing the optimized ED-MS-TiO2 ETL attain an impressive efficiency of 15.63 %, surpassing counterparts utilizing spin-coated TiO2 ETLs, which achieve only 9.70 %.

Fusing Science with Industry: Perovskite Photovoltaics Moving Rapidly into Industrialization.

The organic-inorganic lead halide per materials have emerged as highly promising contenders in the field of photovoltaic technology, offering exceptional efficiency and cost-effectiveness. The commercialization of perovskite photovoltaics hinges on successfully transitioning from lab-scale perovskite solar cells to large-scale perovskite solar modules (PSMs). However, the efficiency of PSMs significantly diminishes with increasing device area, impeding commercial viability. Central to achieving high-efficiency PSMs is fabricating uniform functional films and optimizing interfaces to minimize energy loss. This review sheds light on the path toward large-scale PSMs, emphasizing the pivotal role of integrating cutting-edge scientific research with industrial technology. By exploring scalable deposition techniques and optimization strategies, the advancements and challenges in fabricating large-area perovskite films are revealed. Subsequently, the architecture and contact materials of PSMs are delved while addressing pertinent interface issues. Crucially, efficiency loss during scale-up and stability risks encountered by PSMs is analyzed. Furthermore, the advancements in industrial efforts toward perovskite commercialization are highlighted, emphasizing the perspective of PSMs in revolutionizing renewable energy. By highlighting the scientific and technical challenges in developing PSMs, the importance of combining science and industry to drive their industrialization and pave the way for future advancements is stressed.

Large-Area Perovskite Solar Module Produced by Introducing Self-Assembled L-Histidine Monolayer at TiO2 and Perovskite Interface.

Perovskite solar cells have been proven to enhance cell characteristics by introducing passivation materials that suppress defect formation. Defect states between the electron transport layer and the absorption layer reduce electron extraction and carrier transport capabilities, leading to a significant decline in device performance and stability, as well as an increased probability of non-radiative recombination. This study proposes the use of an amino acid (L-Histidine) self-assembled monolayer material between the transport layer and the perovskite absorption layer. Surface analysis revealed that the introduction of L-Histidine improved both the uniformity and roughness of the perovskite film surface. X-ray photoelectron spectroscopic analysis showed a reduction in oxygen vacancies in the lattice and an increase in Ti4+, indicating that L-Histidine successfully passivated trap states at the perovskite and TiO2 electron transport layer interface. In terms of device performance, the introduction of L-Histidine significantly improved the fill factor (FF) because the reduction in interface defects could suppress charge accumulation and reduce device hysteresis. The FF of large-area solar modules (25 cm2) with L-Histidine increased from 55% to 73%, and the power conversion efficiency (PCE) reached 16.5%. After 500 h of aging tests, the PCE still maintained 91% of its original efficiency. This study demonstrates the significant impact of L-Histidine on transport properties and showcases its potential for application in the development of large-area perovskite module processes.

Transition metals-based electrocatalysts on super-flat substrate for perovskite photovoltaic hydrogen production with 13.75% solar to hydrogen efficiency

Harnessing the inexhaustible solar energy for water splitting is regarded one of the most promising strategies for hydrogen production. However, sluggish kinetics of oxygen evolution reaction (OER) and expensive photovoltaics have hindered commercial viability. Here, an adhesive-free electrodeposition process is developed for in-situ preparation of earth-abundant electrocatalysts on super-flat indium tin oxide (ITO) substrate. NiFe hydroxide exhibited prominent OER performance, achieving an ultra-low overpotential of 236 mV at 10 mA/cm2 in alkaline solution. With the superior OER activity, we achieved an unassisted solar water splitting by series connected perovskite solar cells (PSCs) of 2 cm2 aperture area with NiFe/ITO//Pt electrodes, yielding overall solar to hydrogen (STH) efficiency of 13.75 %. Furthermore, we upscaled the monolithic facility to utilize perovskite solar module for large-scale hydrogen production and maintained an approximate operating current of 20 mA. This creative strategy contributes to the decrease of industrial manufacturing expenses for perovskite-based photovoltaic-electrochemical (PV-EC) hydrogen production, further accelerating the conversion and utilization of carbon-free energy.

Anomalous Electroluminescence Characteristics of Perovskite Modules.

Spatially resolved photoluminescence (PL) and electroluminescence (EL) imaging technologies play a crucial role in evaluating the performance and stability of photovoltaic devices. However, their application in perovskite devices presents unique challenges. In this study, we report a discrepancy between the electrical performance of perovskite solar modules (PSMs) and the EL images. Following the application of a reverse bias voltage, we observed an increase in EL brightness associated with prolonged carrier lifetime and transport length. Furthermore, cross-sectional Kelvin probe force microscopy identified a significant potential increase primarily at the electron-transport layer (ETL) side after reverse bias, suggesting the presence of defective ETL/perovskite interfaces with filled hole traps. To address this EL mismatch, we proposed a mild reverse current recovery method aimed at aligning EL images with the cell performance without compromising device efficiency. This approach effectively mitigates discrepancies, ensuring alignment between the device performance and EL imaging. Our study underscores that caution is required when utilizing EL imaging to monitor spatial homogeneity in PSMs for future industrial production.

Operationally stable perovskite solar modules enabled by vapor-phase fluoride treatment.

The ever-increasing power conversion efficiency of perovskite solar cells has illuminated the future of the photovoltaic industry, but the development of commercial devices is hampered by their poor stability. In this study, we report a scalable stabilization method using vapor-phase fluoride treatment, which achieves 18.1%-efficient solar modules (228 square centimeters) with accelerated aging-projected T80 lifetimes (time to 80% of efficiency remaining) of 43,000 ± 9000 hours under 1-sun illumination at 30°C. The high stability results from vapor-enabled homogeneous fluorine passivation over large-area perovskite surfaces, suppressing defect formation energy and ion diffusion. The extracted degradation activation energy of 0.61 electron volts for solar modules is comparable to that of most reported stable cells, which indicates that modules are not inherently less stable than cells and closes the cell-to-module stability gap.

Large Orientation Angle Buried Substrate Enables Efficient Flexible Perovskite Solar Cells and Modules.

Flexible perovskite solar cells (f-PSCs) have emerged as potential candidates for specific mechanical applications owing to their high foldability, efficiency, and portability. However, the power conversion efficiency (PCE) of f-PSC remains limited by the inferior contact between perovskite and flexible buried substrate. Here, an asymmetric π-extended self-assembled monolayer (SAM) (4-(9H-dibenzo[a,c]carbazol-9-yl)butyl)phosphonic acid (A-4PADCB) is reported as a buried substrate for efficient inverted f-PSCs. Employing this design strategy, A-4PADCB exhibits a significant orientation angle away from the surface normal, homogenizing the distribution of contact potentials. This enhancement improves the SAM/perovskite interface quality, controlling the growth of favorable perovskite films with low defect density and slight tensile stress. Integration of A-4PADCB into small-area f-PSCs and large-area flexible perovskite solar modules with an aperture area of 20.84cm2 achieves impressive PCEs of up to 25.05% and 20.64% (certified 19.51%), respectively. Moreover, these optimized A-4PADCB-based f-PSCs possess enhanced light, thermal, and mechanical stability. This research paves a promising avenue toward the design of SAM-buried substrates with a large orientation angle, regulating perovskite growth, and promoting the commercialization of large-area flexible perovskite photovoltaics.

CsPbI3 perovskite solar module with certified aperture area efficiency >18% based on ambient-moisture-assisted surface hydrolysis

CsPbI3 perovskite solar module with certified aperture area efficiency >18% based on ambient-moisture-assisted surface hydrolysis

Large-Area Perovskite Solar Modules Based on Uniformity Engineering of Perovskite Films: The Critical Role of Methyldiphenylphosphine Oxide Additive.

Perovskite solar cells (PSCs) have led to distinguished achievements and become one of the state-of-the-art photovoltaic technologies. Undoubtedly, reliable preparation of large area high-quality perovskite (PVK) films with uniform optoelectronic properties has become a critical and challenging task to transition PSCs from lab to market. Here, methyldiphenylphosphine oxide (MDPPO) is employed as an additive in a PVK precursor solution to promote uniform conductivity and carrier transport of PVK films. More important, to check its compatibility with the upscaling process, the MDPPO additive strategy was further applied to doctor-blade large-area PVK films. As a result, benefit from the favorable role of MDPPO additive, the power conversion efficiencies (PCEs) of small-area PSCs reach 23.85% with superb open circuit voltage (Voc) of 1.15 V and fill factor of 81.21%, while an impressive PCE of 19.22% was achieved for the large-area PSC minimodules with active area of 61.48 cm2. Remarkably, the MDPPO modified device exhibits significantly improved operational stability, maintaining an initial efficiency of 68% even after 750 h under continuous 1-sun illumination. Our achievements will provide profound insight and further guidance for the scale-up process of PSCs from lab to large-scale modules.

Advancements in Scaling Up Perovskite Solar Cells: From Small-Area Devices to Large-Scale Modules.

The power conversion efficiency (PCE) of perovskite solar cells (PSCs) has exceeded those of conventional thin-film solar cell technologies, and the speed at which this increase has been achieved is unprecedented in the history of photovoltaics. Despite the significant progress achieved by PSCs at the laboratory level, their commercial prospects still face two significant challenges: scaling up in size and ensuring long-term stability. Small-area devices (~1 cm2) are typically fabricated using spin-coating. However, this approach may not be suitable for preparing the large-area (>100 cm2) substrates required for commercialization. Thus, new materials and methods must be developed to facilitate the coating of large-area PSCs. This review will discuss the development of scaling up organic-inorganic hybrid PSCs and the challenges of increasing the device area. Furthermore, it will provide an overview of the methodologies for achieving high-efficiency perovskite solar modules.

Stabilizing Solution–Substrate Interaction of Perovskite Ink on PEDOT:PSS for Scalable Blade Coated Narrow Bandgap Perovskite Solar Modules by Gas Quenching

The development of scalable 1.25 eV mixed Pb–Sn perovskite solar modules by blade coating lags behind Pb‐based perovskites due to limited understanding of solution–substrate interaction of the perovskite ink on PEDOT:PSS and subsequent gas quenching. To address this challenge, the wet film deposition and quenching process to better understand narrow bandgap perovskite film formation on PEDOT:PSS are studied. It is found that the wetting of Pb–Sn perovskite ink on PEDOT:PSS is highly unstable over relevant coating time scales, causing the contact angles to decrease rapidly from 42° to 16° within seconds. This instability leads to localized irregularities in the wet film, resulting in uneven solvent extraction and inhomogeneous nuclei density. As a result, rough perovskite films with voids at the buried interface are obtained. To overcome this problem, a quasistatic wetting process by reducing the blade coating speed is developed, thereby stabilizing the wetting behavior of Pb–Sn perovskite precursor ink on PEDOT:PSS. This optimized process facilitates the deposition of high‐quality, void‐free Pb–Sn perovskite films with uniform thickness over 8 cm of coating length using moderate (1.4 bar) N2 quenching. 20% efficient narrow bandgap perovskite solar cells and minimodules with 15.8% active area efficiency on 15.9 cm2 are achieved.

Highly transparent anti-reflection coating enhances the underwater efficiency and stability of perovskite solar modules

Highly transparent anti-reflection coating enhances the underwater efficiency and stability of perovskite solar modules

Collaborative Fabrication of High-Quality Perovskite Films for Efficient Solar Modules through Solvent Engineering and Vacuum Flash System.

The vacuum flash solution method has gained widespread recognition in the preparation of perovskite thin films, laying the foundation for the industrialization of perovskite solar cells. However, the low volatility of dimethyl sulfoxide and its weak interaction with formamidine-based perovskites significantly hinder the preparation of cell modules and the further improvement of photovoltaic performance. In this study, we describe an efficient and reproducible method for preparing large-scale, highly uniform formamidinium lead triiodide (FAPbI3) perovskite films. This is achieved by accelerating the vacuum flash rate and leveraging the complex synergism. Specifically, we designed a dual pump system to accelerate the depressurization rate of the vacuum system and compared the quality of perovskite film formed at different depressurization rates. Further, to overcome the limitations posed by DMSO, we substituted N-methylpyrrolidone as the ligand solvent, creating a stable intermediate complex phase. After annealing, it can be transformed into a uniform and pinhole-free FAPbI3 film. Due to the superior quality of these films, the large area perovskite solar module achieved a power conversion efficiency of 22.7% with an active area of 21.4 cm2. Additionally, it obtained an official certified efficiency of 22.1% with an aperture area of 22 cm2, and it demonstrated long-term stability.

Surface Engineering of Tin Oxide Nanoparticles by pH Modulation Facilitates Homogeneous Film Formation for Efficient Perovskite Solar Modules (Adv. Energy Mater. 25/2024)

Surface Engineering of Tin Oxide Nanoparticles by pH Modulation Facilitates Homogeneous Film Formation for Efficient Perovskite Solar Modules (Adv. Energy Mater. 25/2024)