A molecular shield against light: Stabilizing perovskite solar cells at record efficiency
KeAi Communications Co., Ltd.
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Hindered amine stabilization suppresses light-induced degradation while enabling record-efficiency perovskite solar cells. Schematic illustration of the hindered amine stabilization strategy (HASS) and its impact on device performance. Under illumination and oxygen exposure, photoexcited electrons in the perovskite generate superoxide radicals (O₂•⁻), which trigger decomposition into MA/FA species, I₂, and PbI₂. Incorporation of a multifunctional hindered amine scavenges these reactive radicals while simultaneously coordinating with Pb²⁺ and iodine vacancy defects, thereby blocking degradation pathways and passivating trap states. The resulting inverted perovskite solar cell achieves a champion power conversion efficiency of 26.74% (certified 26.56%), demonstrating the synergistic role of radical suppression and defect passivation in enhancing both efficiency and light stability.
view moreCredit: Cong Chen
Perovskite solar cells have reached power conversion efficiencies comparable to established photovoltaic technologies, yet their vulnerability to light-induced degradation continues to hinder practical deployment. This study introduces a chemical stabilization strategy that suppresses the radical reactions responsible for photo-driven decomposition in perovskite materials. By integrating a multifunctional hindered amine into the perovskite layer, the approach simultaneously scavenges reactive oxygen species and passivates electronic defects. As a result, the solar cells achieve both exceptionally high efficiency and markedly improved operational durability under illumination. The work demonstrates that controlling light-activated chemical pathways at the molecular level can reconcile efficiency and stability—two long-standing, competing challenges in perovskite photovoltaics.
Metal-halide perovskite solar cells are attractive for next-generation photovoltaics due to their low fabrication cost and rapidly rising efficiencies. However, exposure to light and oxygen generates superoxide radicals that attack organic cations and disrupt the perovskite lattice, leading to rapid performance loss. While encapsulation and optical filtering can mitigate environmental damage, they do not address degradation originating inside the perovskite crystal or at defect-rich interfaces. Moreover, trap states at grain boundaries often accelerate radical formation and non-radiative recombination. Based on these challenges, there is a pressing need to develop strategies that directly suppress light-induced chemical degradation while simultaneously reducing defect density within perovskite films.
Researchers from Hebei University of Technology, Kunming University of Science and Technology, Macau University of Science and Technology, and Chimie ParisTech report a new stabilization approach for perovskite solar cells in eScience, published (DOI: 10.1016/j.esci.2025.100451) in January 2026. The team demonstrates that incorporating a hindered amine light stabilizer into inverted perovskite solar cells effectively blocks photo-induced decomposition pathways. The resulting devices deliver a certified power conversion efficiency above 26% while maintaining performance under prolonged light exposure, offering a promising route toward durable, high-performance perovskite photovoltaics.
The proposed hindered amine stabilization strategy operates through a dual mechanism. Under illumination, the hindered amine absorbs light energy and forms nitroxyl radicals that catalytically neutralize superoxide species generated within the perovskite layer. By removing these highly reactive radicals before they can attack organic cations or Pb–I bonds, the strategy suppresses the primary chemical trigger of light-induced degradation. Importantly, the radical-scavenging process is regenerative, allowing continuous protection during device operation.
In parallel, functional groups within the hindered amine molecule coordinate with under-coordinated lead ions and iodine vacancies at grain boundaries and surfaces. This chemical interaction passivates electronic trap states, enlarges perovskite grain size, smooths film morphology, and reduces non-radiative recombination. Spectroscopic and electrical analyses confirm lower trap densities, longer carrier lifetimes, and improved energy-level alignment at device interfaces.
Together, these effects enable inverted perovskite solar cells fabricated under ambient conditions to reach a champion efficiency of 26.74%. Unencapsulated devices retain over 95% of their initial efficiency after more than 1,000 hours of continuous light aging, demonstrating a rare combination of record efficiency and operational stability.
“This work shows that light instability in perovskite solar cells is not an unavoidable materials problem, but a chemically addressable one,” the researchers note. By targeting both reactive radicals and interfacial defects, the hindered amine approach offers a unified solution rather than a collection of incremental fixes. The authors emphasize that the strategy is compatible with existing device architectures and scalable fabrication methods, making it particularly relevant for translating laboratory advances into commercially viable photovoltaic technologies.
The demonstrated stabilization strategy could significantly accelerate the commercialization of perovskite solar cells, especially for applications requiring long-term exposure to sunlight, such as building-integrated photovoltaics and tandem solar modules. Beyond perovskites, the concept of combining radical scavenging with defect passivation may be applicable to other light-sensitive optoelectronic materials. By reframing stability as a controllable chemical process rather than a structural limitation, this work opens new pathways for designing durable, high-efficiency solar technologies that bridge the gap between laboratory performance and real-world deployment.
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Media contact
Name: Editorial Office of eScience
Email: eScience@nankai.edu.cn
eScience – a Diamond Open Access journal cooperated with KeAi and published online at ScienceDirect. eScience is founded by Nankai University (China) in 2021 and aims to publish high quality academic papers on the latest and finest scientific and technological research in interdisciplinary fields related to energy, electrochemistry, electronics, and environment. eScience provides insights, innovation and imagination for these fields by built consecutive discovery and invention. Now eScience has been indexed by SCIE, CAS, Scopus and DOAJ. Its impact factor is 36.6, which is ranked first in the field of electrochemistry.
Journal
eScience
Article Title
Chemical inhibition of light-induced decomposition by hindered amine for efficient and stable perovskite solar cells
A two-layer strategy pushes perovskite solar cells toward long-term stability
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Mutual stabilization strategy enables efficient and durable perovskite solar cells. Schematic illustration and performance summary of a hybrid–inorganic bilayer perovskite architecture. An ultrathin cubic CsPbI₃ capping layer is deposited on black-phase FAPbI₃, where close lattice matching enables mutual phase stabilization and suppresses ion diffusion at the interface. Compared with conventional 3D and 3D/2D-treated devices, the bilayer structure delivers markedly higher power conversion efficiency and greatly enhanced operational stability, retaining over 94% of its initial efficiency after more than 1,100 hours of continuous operation at 85 °C under simulated sunlight.
view moreCredit: Xiong Li, et al.
A bilayer perovskite strategy improves long-term stability in solar cellsPerovskite solar cells have achieved remarkable efficiencies, yet their practical deployment remains limited by phase instability and ion migration under heat and illumination. This study introduces a bilayer perovskite design that combines a hybrid organic-inorganic absorber with an ultrathin inorganic capping layer to achieve mutual stabilization. By leveraging lattice matching between the two materials, the approach simultaneously preserves the photoactive crystal phase and suppresses detrimental ion diffusion across interfaces. As a result, the bilayer devices deliver record-level efficiency together with exceptional operational stability, demonstrating a viable pathway toward durable, high-performance perovskite photovoltaics.
Organic–inorganic halide perovskites are widely regarded as promising candidates for next-generation photovoltaics because of their tunable bandgaps and high absorption efficiency. Among them, formamidinium lead iodide (FAPbI3) has attracted particular interest due to its favorable optoelectronic properties. However, its photoactive black phase is thermodynamically unstable at room temperature and prone to transformation into non-functional phases under light, heat, or moisture. Existing stabilization strategies, including compositional mixing and surface passivation, often introduce new degradation pathways, including interfacial strain and accelerated ion migration. Based on these challenges, there is a clear need to develop advanced strategies that simultaneously stabilize crystal phases and suppress ion transport through deeper, interface-focused investigations.
Researchers from Huazhong University of Science and Technology, Hainan University, and collaborating institutions report a new perovskite stabilization strategy, published in eScience in 2026 (DOI: 10.1016/j.esci.2025.100449). The team developed a 3D/3D bilayer perovskite structure, in which an ultrathin (~5 nm) cesium lead iodide (CsPbI3) layer is deposited on top of a formamidinium-based perovskite absorber using a vapor-phase co-evaporation process. Unlike conventional low-dimensional surface treatments, both layers retain a three-dimensional perovskite framework, enabling robust structural coupling across the interface.
Structural analyses revealed that strong lattice matching at the interface favors the formation of a photoactive cubic phase in both layers, despite each material being individually metastable under ambient conditions. This interfacial coupling reduces strain, suppresses phase transitions during aging, and maintains structural integrity under prolonged thermal stress. Importantly, the inorganic capping layer also acts as an effective barrier against ion migration, blocking both intrinsic ions and ligand-derived species from diffusing across the interface, one of the primary causes of long-term degradation in perovskite devices.
When integrated into inverted perovskite solar cell devices, the bilayer design delivered a certified power conversion efficiency exceeding 27% for small-area cells, while large-area devices achieved efficiencies close to 25%. Operational stability tests demonstrated that the cells retained over 94% of their initial performance after more than 1,100 hours of continuous operation at elevated temperatures. These results place the devices among the most stable and efficient perovskite solar cells reported to date.
According to the researchers, the key advance is not a single material improvement but the cooperative behavior between two perovskite layers. By allowing the hybrid and inorganic components to stabilize each other through lattice matching, the design avoids many of the degradation pathways that typically limit perovskite devices. The team emphasizes that this approach shifts the focus from compositional complexity to interface control, offering a more universal and scalable route for improving both efficiency and durability in perovskite photovoltaics.
This bilayer stabilization strategy has broad implications for the commercialization of perovskite solar technologies. By addressing phase instability and ion migration simultaneously, the approach moves perovskite devices closer to meeting industrial reliability standards. Beyond single-junction solar cells, the design concept can be extended to tandem photovoltaics and other optoelectronic devices where interface stability is critical. Moreover, the use of vacuum-deposited inorganic layers is compatible with scalable manufacturing processes. Together, these advantages suggest that rationally engineered perovskite interfaces could play a central role in enabling durable, high-efficiency solar modules for real-world energy applications.
###
Media contact
Name: Editorial Office of eScience
Email: eScience@nankai.edu.cn
eScience – a Diamond Open Access journal cooperated with KeAi and published online at ScienceDirect. eScience is founded by Nankai University (China) in 2021 and aims to publish high quality academic papers on the latest and finest scientific and technological research in interdisciplinary fields related to energy, electrochemistry, electronics, and environment. eScience provides insights, innovation and imagination for these fields by built consecutive discovery and invention. Now eScience has been indexed by SCIE, CAS, Scopus and DOAJ. Its impact factor is 36.6, which is ranked first in the field of electrochemistry.
Journal
eScience
Article Title
Mutual stabilization of hybrid and inorganic perovskites for photovoltaics
