A team of researchers has discovered a way to improve the performance and lifespan of solar cells by fixing defects on the surface of “perovskite quantum dots.”
These tiny particles are a key material in next-generation solar cells, known for their ability to convert sunlight into electricity efficiently.
However, the surface of quantum dots often becomes distorted during the production process, which reduces the efficiency and stability of the solar cells.
The research, led by Professor Jongmin Choi from the Department of Energy Science and Engineering at DGIST, was conducted in collaboration with Professor Tae Kyung Lee from Gyeongsang National University and Professor Younghoon Kim from Kookmin University.
Their findings were published in the Chemical Engineering Journal.
Perovskite quantum dots are promising because they are excellent at converting light into electricity and can be produced at a large scale.
However, to make them work in solar cells, the “ligands” on the surface of the quantum dots must be replaced.
This process often damages the surface, causing it to crumple like a piece of paper. These distortions lead to lower performance and shorter lifespans for the solar cells.
To solve this problem, the team developed a new method using short ligands that attach securely to both sides of the quantum dots.
This helps restore the smooth, ordered structure of the quantum dots’ surface, reducing defects and allowing the solar cells to work more efficiently.
By reducing the surface defects, the researchers were able to increase the power conversion efficiency of the solar cells from 13.6% to 15.3%.
Additionally, the solar cells showed greater stability, maintaining 83% of their performance for 15 days—an improvement over previous designs.
Professor Choi explained, “By using these new ligands, we were able to smooth out the surface of the quantum dots and reduce defects, which significantly improved both the efficiency and stability of the solar cells.”
The team plans to continue their research to further stabilize perovskite quantum dots and hopes to apply their findings to other devices that rely on converting light into electricity, such as LEDs and other photoelectric technologies.
This breakthrough could bring us one step closer to more reliable and efficient solar energy in the future.
