Additive-Free Interfacial Strategy Boosts Perovskite Cell Efficiency to 26.25% and Extends Lifetime to 24,800 Hours

XenoSpectrum Japan

Overview

An international team including Seoul, Korea, and Toledo Universities has achieved a certified 25.61% (reported 26.25%) conversion efficiency and an estimated 24,800-hour operational lifetime for perovskite solar cells using a novel, additive-free “Contact-Induced Cation Interaction” (CCI) method. This breakthrough physically manipulates 2D/3D perovskite interfaces to resolve internal crystal distortions and reconstruct an ideal lattice structure, fundamentally enhancing long-term stability without chemical additives. The simple, physical interface control represents a significant step towards commercializing highly efficient and stable perovskite technology, especially for tandem applications.

In Depth

Background

Perovskite solar cells (PSCs) have garnered significant attention as a promising next-generation photovoltaic technology due to their remarkable power conversion efficiencies (PCEs). However, their widespread commercialization has been consistently hampered by issues related to long-term stability and durability, particularly under operational stress from heat and light. Traditional approaches to enhance stability have largely relied on chemical additives, which can sometimes compromise device performance or complicate manufacturing processes. A key challenge has been addressing intrinsic defects and strain within the perovskite crystal structure, which are primary drivers of degradation.

Key Findings / Results

An international research collaboration, involving Seoul National University, Korea University, and the University of Toledo, has introduced a groundbreaking, additive-free method termed “Contact-Induced Cation Interaction (CCI).” This innovative strategy dramatically improves the crystal quality of perovskite solar cells. The CCI method involves the physical contact between 2D and 3D perovskite components, which electromagnetically constrains cation rotation within the 3D crystal. Subsequent thermal annealing fundamentally resolves internal crystal distortions, leading to the reconstruction of an ideal lattice structure and a significant reduction in defect density. As a direct result, PSCs fabricated with this CCI approach achieved a certified power conversion efficiency of 25.61% (with a reported peak efficiency of 26.25%). Crucially, the long-term operational stability was drastically improved, demonstrating an estimated operational lifetime of approximately 24,800 hours under accelerated aging conditions, a substantial advancement over prior technologies.

Technical Significance & Outlook

The CCI method represents a profound technical breakthrough, offering a viable solution to the long-standing stability issues that have been a major impediment to the commercialization of perovskite solar cells. By focusing on physical interface control without the need for chemical additives, this approach also promises to simplify manufacturing processes and potentially reduce production costs. The enhanced stability, particularly the 24,800-hour estimated lifetime, brings perovskite technology closer to the 20-25 year operational lifespan typically expected from commercial solar panels, thereby boosting its real-world viability. This technology is expected to yield significant advantages in high-efficiency tandem solar cells, such as perovskite-silicon tandems, where improved stability of the perovskite component is paramount. Future work will involve scaling up this method for large-area modules and conducting extensive outdoor performance validation to confirm its robustness and versatility in practical applications, ultimately accelerating the deployment of perovskite solar cells as a sustainable energy solution.