Square-Centimeter Solution-Processed Planar CH3NH3PbI3 Perovskite Solar Cells with Efficiency Exceeding 15

Area of Science:

• Materials Science
• Renewable Energy
• Solid-State Physics

Background:

• Perovskite solar cells (PSCs) are a promising photovoltaic technology.
• Achieving uniform, high-crystallinity perovskite films over large areas is crucial for commercialization.
• Controlling grain morphology, such as high-aspect-ratio grains, impacts device performance.

Purpose of the Study:

• To demonstrate the preparation of uniform, high-crystallinity planar perovskite films with high-aspect-ratio grains.
• To evaluate the power conversion efficiency (PCE) of these films in planar perovskite solar cells (PSCs).
• To investigate the scalability of the film preparation method for larger active areas.

Main Methods:

• Fabrication of planar perovskite films with controlled high-aspect-ratio grain structures.
• Deposition techniques ensuring uniformity over a square-inch area.
• Fabrication and characterization of planar perovskite solar cells (PSCs) with active areas of 1.2 cm² and 0.12 cm².
• Performance testing including stabilized power conversion efficiency (PCE) measurements.

Main Results:

• Uniform, high-crystallinity planar perovskite films with high-aspect-ratio grains were successfully prepared over a square-inch area.
• The best power conversion efficiency (PCE) achieved was 16.3% for a 1.2 cm² PSC (stabilized output ≈15.6%).
• A higher PCE of 18.3% (stabilized output ≈17.5%) was obtained for a smaller 0.12 cm² PSC, indicating excellent material quality.

Conclusions:

• The demonstrated method enables the production of high-quality perovskite films suitable for efficient solar cells.
• The results highlight the potential for scalable fabrication of high-performance planar perovskite solar cells.
• Further optimization could lead to even higher efficiencies for large-area perovskite photovoltaic devices.