Scientists have developed a new way to boost the performance of perovskite solar cells by precisely controlling the formation of two-dimensional (2D) perovskite phases at critical interfaces.
Perovskite solar cells are seen as the future of renewable energy because they can be very efficient and low-cost. But the big challenge is keeping the material stable and fixing defects that reduce performance.
Traditionally, researchers have tried to incorporate 2D perovskite structures into the bulk or surface of three-dimensional (3D) perovskite films using long-chain ammonium salts. While this improves stability, achieving 2D structures exclusively at the buried interface, the hidden boundary between the perovskite and its supporting layer has remained elusive.
In the latest study, researchers from the Qingdao Institute of Bioenergy and Bioprocess Technology (QIBEBT) of the Chinese Academy of Sciences, in collaboration with international partners, solved this problem by adding thioglycolic acid and oleylamine (OAm) stepwise to tin dioxide (SnO) nanoparticles. These nanoparticles act as the electron transport layer, and the process creates a new material called SnO-TGA-OAm.
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The strong bond between these molecules ensures that the reaction with formamidinium iodide, a key perovskite ingredient, happens only during heating. This controlled process builds a 2D/3D perovskite structure exactly at the bottom interface, instead of spreading across the whole film.
The 2D layer helps crystals grow more effectively, accelerates the formation of 3D perovskite, and reduces interface defects by more than 10-fold. With fewer defects, the solar cell loses less energy, making it more efficient and stable.
The researchers used new SnO-TGA-OAm nanoparticles as a special layer that helps electrons move more smoothly and improves interconnection within perovskite solar cells. Solar cells made with this layer showed high efficiency: 26.19% for small devices (0.09 cm), 23.44% for medium modules (21.54 cm, certified at 22.68%), and 22.22% for large modules (64.80 cm).
“These values rank among the highest efficiencies reported to date for small-sized PSCs and modules based on 2D/3D perovskite heterojunctions,” noted Dr. ZHAO Qiangqiang, first author of the study.
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By addressing the challenge of making interface-specific 2D perovskite, this research paves the way for large-scale perovskite solar cells. The approach improves efficiency and long-term stability, two hurdles that have slowed the transition of perovskite technology from the lab to market.
“This in situ solid-state ligand-exchange strategy could be easily scalable from lab to factory production while delivering enhanced operational stability,” added Prof. PANG Shuping, a corresponding author of the study.
“It brings the commercialization of PSCs significantly closer to realization.”
Journal Reference:
Zhao, Q., Zhang, B., Hui, W. et al. Buried 2D/3D heterojunction in nip perovskite solar cells through solid-state ligand-exchange reaction. Nat Energy (2026). DOI: 10.1038/s41560-026-01980-4
https://www.techexplorist.com/interface-engineering-boosts-perovskite-solar-cell-performance/102064/
