Field‐Relevant Degradation Mechanisms in Metal Halide Perovskite Modules

Advanced Energy Materials · 2025-03-16 · 10 citations

Abstract Field testing, failure analysis, and understanding of degradation mechanisms are essential to advancing metal halide perovskite (MHP) photovoltaic (PV) technology toward commercialization. Here, we present performance data from up to 1 year of outdoor testing of MHP modules in Golden, Colorado. The module encapsulation architecture and encapsulant materials have a significant impact on module reliability, with modules containing a polyolefin elastomer (POE) in addition to a desiccated polyisobutylene (PIB) edge seal outlasting modules with only a PIB edge seal or PIB blanket. Nondestructive and destructive characterization of the field‐tested modules points to module scribes and interfaces as areas of potential mechanical weakness and chemical migration, resulting in shunt pathways and increased series resistance. Finally, indoor accelerated stress testing with light and elevated temperatures is performed, demonstrating failure with similar scribe degradation signatures as compared to the field‐tested modules. Under both outdoor testing and light and elevated temperature conditions, electrochemical corrosion between the copper electrode and the mobile iodine ions appeared dominant, with a significant progression at the scribes that is speculated to result from an interplay between the initial laser damage and joule heating from enhanced ion diffusion under bias.

In Situ Electrochemistry of Buried Interfaces in Metal Halide Perovskites: Probing Energy Bands, Halide Redox Activity, and Kinetics

Advanced Energy Materials · 2025-09-22 · 1 citations

Abstract Control over charge injection and extraction processes across buried interfaces is fundamental for all (opto)electronic multilayer device platforms, necessitating detailed understanding of local structural and chemical differences that promote defect formation, distort energetic band‐edge alignments, and alter charge transport processes. Herein, the implementation of a low‐cost electroanalytical methodologies’ tool suite is described to quantitatively characterize buried interfaces and redox reactions in printable, mixed electrical–ionic, and redox‐active metal halide perovskites and a prototypical hole‐transporting nickel oxide (NiO x ) thin film. The objective is to demonstrate the power of electrochemical methodologies to improve the nanoscale understanding of complex interfaces within optoelectronic devices by providing case studies on how to: i) differentiate between electronic and chemical properties in NiO x contacts; ii) measure changes in reversibility of halide redox reactions via NiO x surface states; iii) assess energy alignment and charge transport across (modified) buried interfaces; and iv) quantify defects at buried interfaces that change with modifiers and differences in perovskite processing, including increasing defect concentrations when films are slot‐die‐coated versus spin‐cast. The collective approach addresses major challenges in understanding the precise energy landscape and interface reactivity under relevant electric fields that mimic operando conditions (away from equilibrium) and across length scales in thin film device formats.

Screening Metal Halide Perovskite Solar Modules for Premature Field Failures

PRX Energy · 2025-09-22

Developing metal halide perovskite (MHP) photovoltaic (PV) devices into reliable large-area solar modules could accelerate global solar energy deployment. Many MHP devices are susceptible to degradation under light and elevated temperature (LT). Published research on LT testing is limited at the module level, and LT testing has not yet been developed for qualification testing of commercial PV products. This report assesses whether results of LT testing at moderately elevated temperatures correlate with those of field-tested modules from the same batch. Six batches of samples from four manufacturers are assessed. It is shown that modules with a robust package that can maintain over 80% of their peak efficiency during LT testing at 55 °C for 100 h are more likely to retain over 80% of their peak efficiency during outdoor operation for 10 weeks. This finding is a step towards developing a validated test protocol that could be incorporated into a qualification standard for the commercialization of MHP PV technologies.

C ₆₀ -based ionic salt electron shuttle for high-performance inverted perovskite solar modules

Science · 2025-04-17 · 79 citations

Although buckminsterfullerene (C 60 ) is usually the electron transport layer (ETL) in inverted perovskite solar cells (PSCs), its molecular nature leads to weak interfaces that result in nonideal interfacial electronic and mechanical degradation. In this study, we synthesized an ionic salt from C 60 , 4-(1′,5′-dihydro-1′-methyl-2′ H -[5,6] fullereno-C 60 - I h -[1,9-c]pyrrol-2′-yl) phenylmethanaminium chloride (CPMAC), and used it as the electron shuttle in inverted PSCs. The CH 2 -NH 3 + head group in the CPMA cation improved the ETL interface, and the ionic nature enhanced the packing, leading to a ~threefold increase in the interfacial toughness compared with that of C 60 . Using CPMAC, we obtained ~26% power conversion efficiencies (PCEs) with ~2% degradation after 2100 hours of 1-sun operation at 65°C. For minimodules (four subcells, 6 square centimeters), we achieved a PCE of ~23% with <9% degradation after 2200 hours of operation at 55°C.

Author response for "Barrier layer design reduces top electrode ion migration in perovskite solar cells"

2025-04-17

Why are Lead Iodide‐Based Perovskite Precursor Inks Yellow?

Advanced Energy Materials · 2025-10-05 · 3 citations

Abstract A challenge faced by metal halide perovskite (MHP) photovoltaics is scaling up solution deposition processes to realize rapid and inexpensive manufacturing. The challenge lies in completely understanding and controlling solution speciation, nucleation, and self‐assembly of iodoplumbate complexes during solvent evaporation as the liquid transforms into gels and solids. An accurate description of solution species, at all points in the transformation, is a prerequisite to design robust and reliable processes. Here, the common assumption that initial monoplumbate solution species typically invoked (e.g., [PbI 6 ] 4− ) are certainly not the origin of optical absorbance at >400 nm wavelengths is disproved, as are many large particles of common “intermediate” iodoplumbate phases with face‐ or edge‐sharing connectivity. Instead, a new perspective is offered, involving (partially) corner‐sharing iodo(poly)plumbates (>1 Pb 2+ per complex) that experience highly dynamic chemical environments. It is outlined how the MHP field would benefit by elucidating these phenomena. Future work is required to determine the size and kinetic behavior of polyplumbate species, and contextualize these findings in relation to broader trends in materials chemistry beyond MHPs. Ultimately, a complete explanation for the solution speciation, optical absorbance signatures, and the color of MHP precursor inks remains an open challenge to the community.

Barrier layer design reduces top electrode ion migration in perovskite solar cells

EES solar. · 2025-01-01 · 13 citations

We report on an examination of mobile ion concentration ( N 0 ) in perovskite solar cells (PSCs) as a function of temperature and device architecture.

Predicting Trends in <i>V</i> _OC Through Rapid, Multimodal Characterization of State-of-the-Art p-i-n Perovskite Devices

ACS Energy Letters · 2025-11-07

Perovskite photovoltaic technologies are approaching commercial deployment, yet single junction and tandem architectures both still have significant room to improve power conversion efficiency and stability. The ability to perform rapid screening of material quality after altering processing conditions is critical to accelerating the optimization and commercialization of perovskite-based technologies. Currently, researchers utilize a wide range of stand-alone metrology tools to isolate sources of power loss throughout a device stack, which can be slow and labor intensive. Here, we demonstrate the use of a multimodal metrology approach to rapidly determine the maximum achievable and predicted open circuit voltages of >100 perovskite devices during fabrication. Acquisition of these different data is facilitated by combining them into a single integrated measurement platform. We show that these data and automated analysis can be used to rapidly understand and ultimately predict quantitative trends in open circuit voltages of state-of-the-art device architectures. The data and automated analysis workflow presented provides a reliable approach to quickly identify absorber and charge transport layer combinations that can lead to improved open circuit voltages.

Durability research is pivotal for perovskite photovoltaics

Nature Energy · 2025-06-13 · 17 citations

Stress Test Protocols to Screen for Early Field Failures in Metal Halide Perovskite Photovoltaic Modules

2025-06-08

Photovoltaic (PV) modules that have a robust package and that pass a minimum of 100 hours of 1-sun irradiance at 55 °C are more likely to retain 80% of initial efficiency beyond 10 weeks in the field. In this work, we describe our progress towards understanding the relationship between light- and elevated-temperature testing and outdoor degradation of perovskite PV modules. We find that a combination of tests is required to confidently screen for early field failures. Here, we discuss field testing and indoor stress testing results from 8 different module batches representing 4 different module makers and a variety of processing conditions and formulations.