Researchers Vladimir Ivanov, Eduard Ageev, Denis Danilov, Eduard Danilovskiy, and Dmitry Gets from the National University of Science and Technology MISIS in Russia have been investigating ways to improve the stability of mixed halide perovskite solar cells. Their work, published in the journal Solar Energy Materials and Solar Cells, focuses on understanding and mitigating the effects of ion migration within these solar cells.
Perovskite solar cells have shown great promise due to their high efficiency and low production costs. However, their operational stability has been a significant hurdle to commercialization. The researchers identified two main ways ion migration degrades solar cell performance: the Hoke effect and the Schottky effect. Both are triggered by external factors, but they impact the solar cells differently. The Schottky effect rapidly diminishes the charge-carrier separation characteristic, while the Hoke effect slowly accumulates defects in the perovskite layer, enhancing Shockley-Read-Hall recombination.
To study these effects, the researchers measured the time-dependent short-circuit current and various impedance characteristics. They found that increasing the thickness of the transport layer could separate these two effects. A thicker transport layer blocks the loss of charge-carrier selectivity, leading to a substantial increase in the T80 time—the time it takes for the solar cell to degrade to 80% of its initial performance—from just 15 seconds to up to 60 minutes.
This research provides a practical approach to improving the stability of perovskite solar cells, which is crucial for their integration into the energy sector. By understanding and mitigating the Hoke and Schottky effects, the researchers offer a pathway to enhancing the longevity and reliability of perovskite solar cells, making them more viable for large-scale deployment in the renewable energy industry.
This article is based on research available at arXiv.