Stability

Researchers from the Chinese Academy of Sciences (CAS) and Sichuan University have developed an innovative seed-assisted epitaxial growth strategy to stabilize and enhance the photoactive α-phase in perovskite solar cells (PSCs). By introducing pre-synthesized (GABA)₂PbI₄ single crystals (GABA = Gamma-aminobutyric acid) into the 3D perovskite precursor solution, the team achieved preferential and rapid formation of the black α-FAPbI₃ phase at room temperature.

In situ grazing-incidence wide-angle X-ray scattering (GIWAXS) analyses revealed that these (GABA)₂PbI₄ seeds serve as epitaxial templates, accelerating α-phase crystallization while suppressing the formation of the undesired δ-phase. The key lies in the highly matched lattice constants between the seeds and α-FAPbI₃, which reduce the nucleation barrier and guide the film’s vertical orientation.

An international team of researchers, including ones from Iritaly Trading Company, École Polytechnique Fédérale de Lausanne (EPFL), University of Rome Tor Vergata, Argonne National Laboratory and Italy-based Greatcell Solar, has reported a co-crystal engineering approach to improve the long-term stability of perovskite solar cells and modules.

The team used a neutral molecule, benzoguanamine, as a linker in low-dimensional perovskites, replacing conventional ionic molecules, to form a co-crystal. By applying this co-crystal layer onto the perovskite layer, they achieved power conversion efficiency of 23.4% in small-area solar cells, and 23.1% and 18.5% on solar modules with active areas of 9.0 cm² and 48 cm², respectively. The solar modules retained more than 95% and 98% of their initial efficiency after >5,000 h of 1-sun light soaking and >1,000 h of ultraviolet-ray exposure, respectively, at maximum power point conditions. They also retained more than 91% of their initial efficiency after >5,000 h of continuous thermal stress at 85 °C.

Researchers from King Abdullah University of Science and Technology (KAUST), The Chinese University of Hong Kong (Shenzhen), Shaanxi Normal University, Korea University, National University of Singapore, National Technical University of Athens and University of Manchester have reported a method to enhance both the efficiency and stability of perovskite solar cells (PSCs).

The research team achieved this by fine-tuning the molecules that coat the perovskite surfaces. They utilized specially designed small molecules, known as amidinium ligands, which act like a molecular “glue” to hold the perovskite structure together.

Researchers from Zhejiang University, Huaneng Clean Energy Research Institute and Soochow University developed a novel strategy to tackle one of the biggest barriers to perovskite solar commercialization - long-term outdoor stability. By introducing an amorphous–crystalline silicon nitride (Si₃N₄) nanocomposite at the buried interface of perovskite solar cells, the team effectively curbed charge accumulation and defect evolution, two major factors behind performance degradation.

The amorphous shell of the nanocomposite passivates surface defects, while the crystalline core traps excess charge carriers, enhancing the internal electric field and charge extraction efficiency. As a result, the optimized perovskite cells achieved an impressive power conversion efficiency of 26.65% (certified 26.37%), with minimodules reaching 23.17% (certified 22.2%). Even large-area modules (1,252 cm²) maintained stable output for over six months of continuous outdoor operation, marking a major step forward toward durable, high-efficiency perovskite photovoltaics.

Researchers from the University of North Carolina at Chapel Hill and University of Colorado Boulder have examined why perovskite solar cells tend to break down under prolonged heat and sunlight, especially ultraviolet light, and revealed a strategy to dramatically slow that damage. The work focuses on a thin “interlayer” that sits between the electrode and the perovskite material inside a solar cell. This layer is only a single molecule thick, but can play an important role in how long the device lasts.

Reducing reaction at the PA-SAM–perovskite interface through stronger molecular anchoring. Image from: Science

“These interlayers are meant to help charges move efficiently out of the perovskite and into the circuit,” said Chengbin Fei, first author of the study and a postdoctoral researcher in UNC’s Department of Applied Physical Sciences. “But we found that some of the same chemical features that make them useful can also cause long-term damage if they’re not tightly attached to the electrode.”

Researchers from Jinan University, Guangdong Mellow Energy and Shanghai Jiao Tong University have reported a flexible perovskite solar cell architecture that combines data‑driven machine‑learning optimization with a targeted passivation scheme based on amorphous grain‑boundary engineering to simultaneously address power conversion efficiency, operational stability and mechanical reliability. The perovskite microstructure is tailored to suppress nonradiative recombination, mitigate ion‑migration pathways and enhance fracture tolerance under repeated bending, enabling flexible devices with high efficiency, extended durability under environmental stressors and robustness suitable for lightweight, large‑area modules for wearable, vehicular and building‑integrated photovoltaic applications.

The optimized architecture delivers flexible perovskite solar cells with a power conversion efficiency of 24.52%, while maintaining 92.5% of the initial efficiency after 10,000 bending cycles, 95% after 300 days in ambient conditions and 80% after 650 h of continuous maximum power point tracking. Certified flexible modules reach 21.09% efficiency at an aperture area of 21.07 cm² and 17.38% at 0.5 m² (86.9 W output), while a larger 1.4725 m² module delivers 226 W with a specific power of 558 W kg⁻¹, underscoring the scalability of the amorphous grain‑boundary engineering approach. These metrics collectively show that the strategy both advances the state of the art in flexible perovskite device efficiency and mitigates key reliability bottlenecks that have historically impeded the transition to large‑area, application‑relevant modules.

Researchers from AMOLF, the University of Pavia, and the University of Potsdam have introduced a new way to study mobile ions in perovskite solar cells, a factor that strongly influences how these devices age and lose performance. Understanding and controlling such ions is considered crucial for improving the long‑term stability of perovskite technology.

The technique draws inspiration from freezing water: when the device is cooled, the ions effectively “freeze” in place and stop migrating through the material.
Before cooling, the team first drives the ions toward one side of the device with an applied voltage; when the cell is warmed again, the ions “thaw” and drift back, generating a measurable electrical current because of their charge. By analyzing this current, the researchers can determine how many mobile ions are present and how strongly they are bound inside the perovskite layer.

Researchers from the National University of Singapore (NUS), Agency for Science, Technology and Research (A*STAR) and Trina Solar have reported a new vapor-deposition method that improves the long-term and high-temperature stability of perovskite-silicon (Si) tandem solar cells.

The team stated that this is the first time vapor deposition has been successfully applied to industrial micrometer-textured silicon wafers, the actual wafer structure used in commercial solar cells manufacturing, marking a milestone for translating laboratory-scale tandem solar cells into real-world products.

Researchers from RenShine Solar, Nanjing University, the University of Stuttgart, the University of Victoria, and other partners have addressed a long-standing challenge in perovskite solar cell production: the limited operational stability caused by toxic solvents used to dissolve perovskite crystals into inks. These inks, which can be printed, coated, or sprayed like paint, often lead to quality fluctuations when applied to large surfaces.

"Our study addresses these challenges,” says Prof. Michael Saliba, who co-authored the publication and is the head of the Institute for Photovoltaics (ipv) at the University of Stuttgart. "We have successfully demonstrated how the large-scale production of high-performance perovskite PV modules can be carried out in an environmentally friendly, reliable way and under ambient air conditions.”

Researchers from Zhengzhou University, University of Surrey, Chinese Academy of Sciences, Wuhan University of Technology, University of Cambridge and University of Electronic Science and Technology of China (UESTC) have developed flexible perovskite solar modules (f-PSMs) using single-walled carbon nanotubes (SWCNTs) as window electrodes. 

Flexible perovskite solar modules are considered promising for lightweight and sustainable energy generation, but their commercial development has been constrained by limited long-term stability and reliance on indium tin oxide (ITO) electrodes. The research team demonstrated that SWCNT-based electrodes can deliver power conversion efficiencies (PCEs) exceeding 20% at module scale. Further improvement was achieved by treating the SWCNTs with sulfuric acid (H₂SO₄), which enhanced their conductivity and facilitated the formation of a compact NiSO₄–NiOx interface. This interface improves charge transfer between the perovskite absorber and the hole transport layer, enabling ITO-free perovskite solar cells to reach efficiencies above 24% in rigid configurations and about 23% in flexible modules.