Summary: This review paper focuses on the operational stability of perovskite solar cells (PSCs), identifying their short operational lifetime as a major barrier to commercialization despite high efficiency and low cost. It aims to summarize recent advances and effective strategies for improving device lifetime by analyzing underlying mechanisms across different PSC layers, discussing chemical reactions, photo-physical management, and technological modifications. The review also covers emerging standards for testing and reporting stability, providing guidance for future research and development to promote PSC commercialization.

Summary: This review article comprehensively examines the degradation mechanisms of metal halide perovskite solar cells when exposed to moisture, oxygen, heat, light, mechanical stress, and reverse bias. It further details strategies to enhance stability, including perovskite compositional tuning, the application of hydrophobic coatings, the substitution of metal electrodes with carbon or transparent conducting oxides, and improved packaging techniques. The article concludes by offering recommendations for accelerated testing protocols to foster the development of highly efficient and stable solar cells.

Summary: This review focuses on improving the long-term operational stability of perovskite solar cells (PSCs), addressing their short lifespan despite high efficiencies. It elaborates on predominant degradation pathways and mechanisms under operating stressors, and summarizes strategies for enhancing durability through fundamental materials, interface designs, and device encapsulation. The paper also discusses limitations in stability assessment and potential applications, offering proposals for material processing, film formation, interface strengthening, structure design, and encapsulation to promote commercialization.

Summary: This review focuses on enhancing the long-term operational stability of perovskite solar cells (PSCs), addressing degradation triggered by moisture, oxygen, light, and heat. While encapsulation mitigates moisture and oxygen issues, the paper emphasizes material and interfacial improvements for light and heat degradation. It elucidates degradation mechanisms within device layers and interprets strategies for stability enhancement, including compositional engineering (e.g., site-based substitution in the perovskite lattice) and interfacial engineering (e.g., doping charge transport layers, passivation with various materials like quantum dots and low-dimensional perovskites, and protective layers), aiming to guide the optimal design of high-efficiency and stable PSCs.

Summary: This review article provides a comprehensive overview of the latest advances in perovskite solar cells (PSCs), focusing on materials, fabrication techniques, and stability enhancement strategies. It highlights recent progress in perovskite crystal structure engineering and device construction that has improved photo conversion efficiency, while also discussing challenges related to poor stability under ambient conditions. Key strategies to enhance stability, such as employing novel materials for charge transport layers and advanced encapsulation techniques to protect against moisture and oxygen, are discussed, alongside the potential of tin-based PSCs and the mechanical stability of flexible devices.

Summary: This critical review examines the significant progress in perovskite solar cell (PSC) efficiency while highlighting stability as a major hurdle for commercialization. It discusses the inherent vulnerabilities of perovskites to environmental factors such as moisture, heat, and UV light, as well as degradation associated with charge transport layers. The paper critically evaluates various mechanisms of instability and recent engineering techniques employed to enhance device longevity, comparing different approaches and degradation pathways. Furthermore, it addresses the need for standardized stability testing criteria and concludes by emphasizing future research directions, including the development of lattice-matched, stable materials for device layers and the implementation of effective encapsulation methods.

Summary: This review provides an overview of current efforts to enhance the stability of perovskite solar cells (PSCs), acknowledging that while power conversion efficiency has increased significantly, poor stability remains a major barrier to commercialization. The paper summarizes the causes and mechanisms of degradation and categorizes strategies for improving device stability, covering aspects such as structural effects, the photoactive layer, hole- and electron-transporting layers, electrode materials, and device encapsulation, while also touching upon the economic feasibility of PSCs.

Summary: This review focuses on perovskite solar cells (PSCs), highlighting their potential for commercialization due to high efficiency and low cost, but identifies stability as a major hurdle. It summarizes the primary degradation mechanisms in PSCs and discusses key findings related to achieving sufficient stability to meet International Electrotechnical Commission (IEC) standards, while also examining limitations of current IEC assessment frameworks and the significance of outdoor testing for commercialization.

Summary: This review article examines the critical challenge of achieving operational stability in perovskite solar cells (PSCs) comparable to silicon photovoltaics, particularly under practical conditions like maximum power point tracking at 1 sun illumination. It delves into the fundamental causes of perovskite instability, including chemical decomposition pathways triggered by light soaking and electrical bias, and highlights the role of ion migration and trapped charges in permanent degradation. The review also discusses recent advancements and strategies aimed at mitigating these degradation issues to enable the practical use of perovskite-based solar devices.

Summary: This review paper focuses on the critical challenge of long-term operational stability in perovskite solar cells (PSCs), which currently hinders their commercialization despite rapid efficiency gains. It emphasizes the importance of understanding various degradation mechanisms before implementing remedies and discusses different steps and approaches taken to enhance stability. The review highlights recent insights into degradation pathways and stability enhancement strategies, with a particular emphasis on reports that meet operational standards for practical application in commercial solar modules, including discussions on IEC standards.

Summary: This work provides a summary of degradation mechanisms pertinent to perovskite photovoltaics, examining these issues across different scales from individual layers to tandem solar cells and complete solar modules, and outlines corresponding mitigation strategies aimed at achieving reliable solar module performance.

Summary: This review discusses the mechanisms and suppression of photoinduced degradation in perovskite solar cells (PSCs), highlighting that while PSCs achieve high efficiencies, their operational lifespans are significantly limited by stability issues under illumination. The paper details how light radiation can cause phase segregation or chemical decomposition in the perovskite active layers, introduce defects at interfaces with oxide electron transport layers (ETLs), and lead to poor photostability and dopant diffusion in small molecule hole transport layers (HTLs). It emphasizes that photoinduced degradation affects all functional layers and their interfaces, providing an overview to guide further research and optimization for improved device stability.

Summary: This paper reviews the degradation mechanisms of perovskite solar cells (PSCs), noting their impressive performance but lagging longevity compared to silicon technology due to environmental factors such as moisture, heat, and light. It emphasizes that systematically elucidating and eliminating these degradation pathways is crucial for the technology's success and highlights the utility of in situ techniques for tracking real-time structural, compositional, morphological, and optoelectronic changes to overcome statistical variations in degradation studies.

Summary: This review paper discusses the critical challenge of achieving long-term operational stability in perovskite solar cells (PSCs), which is a bottleneck for real-world applications despite significant efficiency breakthroughs. It highlights moisture and oxygen ingress as primary degradation sources and interprets their mechanisms in perovskite absorbers and charge transporting layers. The paper categorizes primary mitigation strategies, including encapsulation, interfacial layer engineering, process engineering, ion engineering, and dopant/alternative engineering, to simultaneously enhance efficiency and stability, while also reviewing materials development and identifying obstacles to high stability.

Summary: This review discusses the rapid progress in perovskite solar cells (PSCs), noting their desirable photovoltaic properties and significant efficiency gains, but highlights that poor long-term stability remains a major limitation for commercialization. The paper aims to discuss the degradation mechanisms affecting perovskite materials and PSCs, and summarize strategies for enhancing their stability, providing insights for future development in the field.

Summary: This review article examines progress in barrier designs for perovskite solar cells (PSCs) to enhance long-term operational stability, a critical bottleneck for commercialization. It discusses how integrated barriers protect the perovskite and functional layers from detrimental external factors like heat, light, moisture, and oxygen, while also preventing internal ion/molecular diffusion. The review categorizes barriers by their functions, locations within the device, and material characteristics, detailing their preparation methods, properties, and impact on device stability, and concludes with predictions for future barrier development.

Summary: This paper provides insights into the factors and mechanisms that cause degradation in perovskite solar cells, and it discusses potential solutions to improve their long-term operational stability.

Summary: This review discusses the critical challenge of degradation and inferior long-term stability in perovskite solar cells (PSCs), which hinders their commercialization despite high power conversion efficiencies. It covers degradation mechanisms and stability studies using experimental and theoretical approaches. The paper summarizes strategies for enhancing PSC stability, including perovskite material engineering, the use of substituted organic and inorganic materials for hole transport, alternative electrodes, interfacial modification, novel device structures, and encapsulation techniques, while also highlighting future directions.

Summary: This paper reviews recent developments in stabilizing perovskite solar cells (PSCs), acknowledging their high power conversion efficiencies but persistent challenges in long-term stability. It discusses interface engineering, electrode materials, and the factors contributing to PSC degradation. The review also highlights carbonaceous materials as alternatives to noble metals in carbon-based PSCs and considers flexible PSCs for wearable electronics, concluding with future perspectives for commercialization.

Summary: This study developed a composite encapsulation strategy, involving sequential deposition of Al2O3 and a fluorosilane layer, to enhance the operational stability of perovskite solar cells (PSCs) by preventing moisture permeation and organic compound volatilization. The research systematically investigated the stability of encapsulated PSCs under simulated operational conditions, including ambient air storage, continuous light illumination, a double 85 condition (85 °C, 85% humidity), and even water immersion, demonstrating superior sealing properties and no significant performance decline. The findings also noted that perovskite decomposition induced by heat or light was reversible in a well-encapsulated environment, attributed to a balance between decomposition and reverse synthesis, paving the way for scalable and robust encapsulation for PSCs.

Summary: This review examines the historical evolution and relationship between efficiency and stability in perovskite solar cells (PSCs), alongside their environmental impacts using Life Cycle Assessment studies. It concludes that PSCs can be widely deployed if their stability is improved to match existing market technologies, highlighting the critical need to mitigate moisture and oxygen degradation. Key recommendations for enhanced stability include employing metal oxides, ternary or quaternary cations, the 2D/3D approach, and effective encapsulation, while also emphasizing recyclability, low-impact industrial processes, and end-of-life considerations.

Summary: This review focuses on interface engineering as a critical strategy for enhancing the efficiency, stability, and reducing hysteresis in perovskite solar cells (PSCs). It details the role of interfaces in PSCs, discusses the origins of interfacial non-radiative recombination (NRR) such as interface defects, imperfect energy level alignment, and interfacial reactions, and analyzes their impact on device performance. The paper outlines mitigation strategies including defect passivation, energy level alignment modulation, and suppression of interfacial reactions, emphasizing the role of interface modifiers, and concludes with an outlook for achieving long-term operational stability through these interface engineering approaches.

Summary: This review offers a comprehensive understanding of degradation mechanisms inherent to perovskites and summarizes effective strategies aimed at advancing the commercialization of perovskite photovoltaic technology.

Summary: This study investigates improving the thermal stability of perovskite solar cells (PSCs) by incorporating a polystyrene-co-polyacrylonitrile (SAN) copolymer within the perovskite layer. The addition of SAN significantly enhances thermal stability by suppressing the migration of organic cations, specifically methylammonium (MA+), which is identified as a key factor in thermal degradation. PSCs with incorporated SAN maintained 85-95% of their power conversion efficiency (PCE) after 24 hours of thermal aging at 100 °C, compared to pure methylammonium lead iodide (MAPI). This improvement is attributed to the suppression of ionic currents at grain boundaries, likely due to the immiscibility between SAN and MA+ components, demonstrating the potential of polymer grain encapsulation for enhancing PSC thermal stability.

Summary: This paper reviews progress in additive engineering for perovskite solar cells (PSCs), focusing on its role in enhancing crystallization, defect passivation, and interface tuning. It categorizes additives into Lewis acids, Lewis bases, ammonium salts, low-dimensional perovskites, and ionic liquids, and summarizes strategies for interface optimization, including modifiers for electron- and hole-transport layers and perovskite surface properties, providing an outlook on future research trends.

Summary: This review discusses the significant efficiency advancements in perovskite solar cells (PSCs) and highlights that current key issues involve further efficiency improvements and long-term operational stability. The paper focuses on strategies to increase open-circuit voltage by enhancing charge-selective contacts and charge carrier lifetimes through methods like ion tailoring. It also addresses challenges in long-term stability, including the impact of testing protocols, ionic movement, and methods to counteract degradation.

Summary: This review focuses on advancements in developing functional electron and hole transporting materials that contribute to both high efficiency and long-term stability in perovskite solar cells (PSCs). It highlights strategies that enhance charge diffusion and suppress ion/molecule diffusion, which are critical for overcoming the intrinsic instability of perovskite materials under outdoor conditions. The paper also reviews interface engineering methods for controlling these diffusion processes and identifies key research areas in charge transporting materials and interface engineering as crucial for achieving stable and efficient PSCs.

Summary: This review discusses the application of self-assembled monolayers (SAMs) for interface engineering in perovskite solar cells (PSCs) to enhance both power conversion efficiency (PCE) and long-term stability, which is identified as a major obstacle for market adoption. The paper details how SAMs are deposited, how they fine-tune optoelectronic properties, improve surface morphology, optimize energy band alignment, reduce interfacial charge recombination, and passivate traps, all contributing to better PCE and stability, and concludes with an outlook on future opportunities for SAMs in PSC development.

Summary: This review summarizes the advancements in inorganic electron transport materials (ETMs) for perovskite solar cells (PSCs), highlighting the significant improvements in PSC power conversion efficiency and long-term stability. It examines prevalent inorganic ETMs like TiO2, SnO2, and ZnO, detailing their synthesis, preparation methods, and application in tandem devices, alongside emerging trends. The paper also discusses strategies for optimizing ETL performance, their impact on J-V hysteresis, and their role in long-term stability, concluding with current challenges and future development prospects.

Summary: This paper reviews recent advancements in perovskite solar cells (PSCs), highlighting their rapid efficiency gains driven by fabrication strategies like device structure optimization, interfacial engineering, chemical tuning, and crystallization control, which have brought efficiencies close to silicon solar cells. However, it identifies device stability as a major impediment to commercialization and states the paper will summarize current research on degradation mechanisms and strategies for enhancing PSC stability.

Summary: This paper investigates the critical challenges, or bottlenecks, that prevent organometal halide perovskite solar cells from achieving the necessary long-term operational stability for widespread commercial adoption.

Summary: This paper provides a comprehensive review of encapsulation strategies for perovskite solar cells (PSCs), examining both external methods to prevent moisture and oxygen intrusion and internal approaches aimed at enhancing the intrinsic stability of the constituent layers.

Summary: This paper provides a comprehensive review of recent advancements in passivation and morphology engineering techniques applied to halide perovskite films, aiming to achieve high efficiency and stability in perovskite solar cells.

Summary: This review focuses on the development of low-temperature processing strategies for fabricating highly stable perovskite solar cells (PSCs) and modules, which are crucial for reducing production costs and enabling applications like flexible devices and tandem cells. The paper introduces major degradation processes in PSCs and discusses the effectiveness of low-temperature processing routes for various materials, summarizing developments, evolving strategies, and their correlation with stability.

Summary: This review, covering 2010-2021 with a focus on recent literature, details advancements in charge transport layers for perovskite solar cells (PSCs), which are crucial for enhancing both stability and efficiency. It discusses the influence of various organic and inorganic materials used in transport layers, including modifications through doping and surface functionalization, and highlights the challenges these strategies pose to long-term stability and commercialization, alongside mechanical challenges and abatement strategies related to these layers.

Summary: This review highlights the significant challenge of long-term operational stability for perovskite solar cells (PSCs), particularly those using inorganic-organic halide lead perovskite absorbers, under real-world conditions like temperature, humidity, and UV irradiation. It discusses the sources of chemical instability, including humidity, phase, thermal instability, and ion migration, and explores strategies for enhancing PSC stability without compromising power conversion efficiency, focusing on additive engineering with surface passivation and composition engineering.

Summary: This review paper focuses on the thermal stability of methylammonium lead halide based perovskite solar cells (PSCs), identifying thermal instability as a major bottleneck for their widespread adoption, especially given that operating temperatures can significantly exceed ambient conditions. While acknowledging that light, oxygen, and moisture-induced degradation can be mitigated by barrier or interface layers, the paper specifically highlights the inherent thermal instability of the common CH3NH3PbI3 (MAPbI3) absorber material, even in inert environments. It reviews recent advances and summarizes promising strategies aimed at overcoming thermal degradation challenges in PSCs.

Summary: This review article surveys recent progress in perovskite solar cell (PSC) components, highlighting breakthroughs in absorbed layer engineering, electron and hole transport layers, and interface materials. It examines novel perovskite compositions, crystal structures, and manufacturing techniques aimed at enhancing stability and scalability, while also evaluating strategies to improve charge carrier mobility and reduce recombination for large-scale photovoltaic applications.

Summary: This study demonstrates that cation compositional engineering in methylammonium lead iodide perovskites can lead to a controlled defect concentration of 10^14 cm^-3 and a thermally stable perovskite film. Devices fabricated using this approach retained approximately 92% of their initial power conversion efficiency (PCE) when operated at temperatures exceeding 75 °C for over 1000 hours.

Summary: This paper reviews current popular and efficient strategies specifically aimed at improving the long-term stability of perovskite solar cells (PSCs) by providing protection against moisture.

Summary: This review discusses recent advancements in metal oxide charge transport layers (ETLs and HTLs) for perovskite solar cells (PSCs), emphasizing their role in achieving high efficiency and improved stability, particularly when prepared under mild deposition conditions and used in devices with both top and bottom metal oxide layers. It covers various approaches like doping, surface treatments, and interface modifications to enhance device performance and briefly touches upon characterization techniques relevant to understanding device mechanisms.