In a groundbreaking advancement for the realm of lightweight and flexible photovoltaic technology, researchers have unveiled a novel approach to overcome longstanding challenges in flexible perovskite solar cells. Perovskite photovoltaics have captivated the renewable energy community due to their high efficiency and potential for cost-effective manufacturing. However, their transition from rigid substrates to flexible formats has been hindered by persistent issues in performance, stability, and mechanical resilience. These limitations have restrained the widespread adoption of flexible solar cells in commercial and large-scale applications despite their alluring properties.
Historically, strategies to enhance the efficiency of perovskite solar cells, such as enlarging the grain size or utilizing lead iodide passivation, have inadvertently compromised their mechanical strength and durability. This trade-off has posed a formidable barrier, as improving optoelectronic properties often came at the cost of structural integrity during bending and prolonged use. Addressing this delicate balance required an inventive solution that could simultaneously elevate performance metrics while safeguarding flexibility and longevity.
The research team led by He, Ma, Wu, and colleagues has introduced a cutting-edge method dubbed “amorphous grain boundary engineering” to fundamentally reimagine the microstructure of flexible perovskite films. By deploying β-cyclodextrin derivatives—complex carbohydrate molecules known for their unique molecular cavities—they were able to orchestrate the formation of self-assembled amorphous grain boundaries within the perovskite layer. These amorphous regions act as passivation sites that significantly mitigate charge recombination, one of the chief efficiency bottlenecks in perovskite solar cells.
Critically, the engineered grain boundaries exploit multiple non-covalent interactions, including coordination bonds, robust hydrogen bonding frameworks, and intricate host–guest molecular dynamics. This triad of chemical interactions not only enhances electronic properties by reducing defects and trap states but also imparts remarkable mechanical toughness. The harmonious integration of these molecular forces results in films that maintain their structural coherence under extensive mechanical deformation, a vital attribute for flexible photovoltaics.
The performance metrics showcase the transformative impact of this strategy. Flexible solar cells fabricated using this approach have achieved a power conversion efficiency of 24.52%, a figure that rivals or surpasses many state-of-the-art rigid perovskite devices. Beyond mere efficiency, these devices exhibit extraordinary durability: retaining 92.5% of their initial efficiency even after 10,000 bending cycles—a level of mechanical endurance rarely attained in the field. This endurance signals a substantial leap towards practical flexible solar technologies capable of enduring real-world conditions.
Stability under ambient conditions is another critical factor for commercial viability. The newly developed perovskite cells retain 95% of their efficiency after 300 days of exposure to ambient air, a staggering improvement relative to typical perovskite devices that degrade rapidly due to moisture and oxygen sensitivity. Additionally, under constant maximum power point tracking, which simulates continuous operation, devices sustained 80% of their initial performance after 650 hours, illustrating robust operational stability.
Scalability remains a pivotal challenge in flexible photovoltaics, as translating laboratory-scale efficiencies to larger areas often leads to performance drops. The authors have compellingly addressed this by engineering modules with aperture areas extending to half a square meter and beyond. Modules measuring 21.07 cm² demonstrated certified efficiencies of 21.09%, while larger format modules of 0.5 m² achieved 17.38%, producing an output power of 86.9 W. Impressively, their largest module spanning 1.4725 m² delivered a power output of 226 W, pushing the envelope in large-area flexible perovskite technology.
One of the most outstanding characteristics of these modules is their exceptional power-to-weight ratio, reaching 558 W per kilogram. This metric underscores the inherent advantages of flexible perovskite technology—lightweight, high power generation combined with mechanical flexibility—making them ideal candidates for emerging applications such as wearable electronics, portable power sources, and integration into vehicles or building materials where weight constraints are paramount.
The amalgamation of data-driven machine learning techniques with chemical passivation strategies highlights the increasingly interdisciplinary nature of modern materials science. By leveraging computational predictions to guide the selection and design of β-cyclodextrin derivatives, the team streamlined the identification of optimal additives that facilitate effective grain boundary formation and passivation. This fusion of experiment and theory exemplifies how digital tools can accelerate innovation in photovoltaic design.
This advance represents a paradigm shift in how perovskite solar cells can be engineered to simultaneously meet the rigorous demands of mechanical flexibility, environmental stability, and high photovoltaic performance. The ability to fabricate large-area, lightweight, and durable modules enhances the prospects for flexible perovskite solar cells to transition from niche applications to mainstream energy harvesting solutions.
Moreover, these findings open fertile ground for further exploration into amorphous grain boundaries and their role in other thin-film semiconductors. The concept of using molecularly tailored additives to tune microstructural and interfacial properties offers a versatile platform potentially translatable to diverse optoelectronic devices, including light-emitting diodes and photodetectors.
While challenges remain—such as optimizing encapsulation techniques and establishing scalable manufacturing routes—the clearly demonstrated improvements in efficiency, stability, and mechanical resilience mark substantial progress toward flexible solar technologies that marry functionality with practicality. This breakthrough could accelerate the adoption of perovskite photovoltaics in flexible electronic devices, smart textiles, and new generations of portable energy systems.
In sum, the research encapsulates a sophisticated approach to surmount critical bottlenecks in flexible perovskite photovoltaics through precision grain boundary engineering facilitated by molecular self-assembly. The interdisciplinary methodology coupled with scalable fabrication offers a blueprint for future innovations seeking to harness the full promise of perovskite solar technology.
The implications of these results extend beyond academic interest, touching on global energy sustainability goals by enabling high-performance, affordable, and lightweight solar power solutions that can be deployed in regions and applications inaccessible to rigid solar panels. As the field progresses, the integration of machine learning and molecular chemistry in materials design will undoubtedly continue to unveil new horizons in energy harvesting technologies.
The potential for commercialization appears imminent, given the demonstrated robustness and efficient energy conversion in flexible formats, which historically lagged well behind rigid counterparts. This advancement thus represents a decisive step toward truly versatile, resilient, and high-efficiency solar cells, heralding a new era for perovskite photovoltaics on flexible substrates.
Subject of Research: Flexible perovskite photovoltaics, grain boundary engineering, molecular passivation, scalable solar modules, mechanical durability, stability enhancement.
Article Title: Amorphous grain boundary engineering for scalable flexible perovskite photovoltaics with improved stability.
Article References:
He, M., Ma, Y., Wu, S. et al. Amorphous grain boundary engineering for scalable flexible perovskite photovoltaics with improved stability. Nat Energy (2026). https://doi.org/10.1038/s41560-025-01932-4
DOI: https://doi.org/10.1038/s41560-025-01932-4
Tags: advancements in flexible energy solutionsamorphous grain boundary engineeringbending durability of solar technologycost-effective solar cell manufacturingenhancing mechanical resilience in solar cellsflexible perovskite solar cellshigh efficiency renewable energy solutionsinnovative microstructure for solar filmslightweight photovoltaic technologyovercoming performance limitations in photovoltaicsstability of perovskite photovoltaicsstructural integrity of flexible solar cells
