The commercialization of perovskite solar cells is expected to be accelerated by the use of inexpensive tin chloride.

UNIST (President Jong-Rae Park) announced on the 2nd that a joint research team including Professor Dong-Seok Kim of the Carbon Neutral Graduate School and Dr. Im-Hyeon Cho of the Korea Institute of Energy Research increased the stability of perovskite solar cells by reacting inexpensive tin (IV) chloride on tin oxide.

In order to achieve high efficiency in perovskite solar cells, it is important to control surface defects in the electron transport layer, a thin film that helps electrons flow smoothly. These defects have a significant impact not only on the efficiency of the solar cell but also on its stability.

The research team dissolved tin chloride in water and applied it to the oxide layer. The tin hydroxide formed during the treatment completely oxidized the upper layer of the tin oxide, and the acid caused recrystallization, improving electron mobility.

Chemical solution deposition is a technology that forms a tin oxide layer, and naturally creates defects on the surface. This is because the tin is not completely oxidized. The process of reducing defects after forming a thin film is a key technology that simultaneously secures high efficiency and long-term stability.

In order to commercialize perovskite solar cells, passing various certification tests is essential. The research team improved the electron transport layer to increase the efficiency of the device and demonstrated that it can withstand long-term heat and ultraviolet rays.

Professor Kim Dong-seok said, “Through this research, we succeeded in suppressing the agglomeration of tin oxide and increasing its crystallinity,” and explained, “This technology will play an important role in increasing the stability of solar cells.”

Researchers Song Ji-won and Dr. Shin Yun-seop said, “We expect to bring about positive changes to the energy industry by simultaneously realizing high efficiency, high strength, and low cost using inexpensive tin chloride.”

The study results were published online on July 3 in Advanced Energy Materials.