Perovskite solar cells, with their ever-increasing power conversion efficiency, have illuminated the future of the photovoltaic industry, but their poor stability has hindered the development of commercial devices.

Here, Guo Wanlin, Academicians and colleagues from Nanjing University of Aeronautics and Astronautics, report a scalable stabilization method using gas phase fluoride treatment, which achieves 18.1% efficiency of a solar module (228 square cm) under one solar irradiation at 30 ° C. Accelerated aging predicts a T80 lifetime (reaching 80% of residual efficiency) of 43,000± 9,000 hours. The related paper was published in Science on July 25, 2024 under the theme "Operationally stable perovskite solar modules enabled by vapor-phase fluoride treatment."

Here, the researchers developed a scalable gas-phase fluorination process to uniformly stabilize the perovskite surface under atmospheric pressure. Unlike solution-based methods, gas phase fluorination enables a uniform distribution of reactants throughout the film surface and forms a solid chemical bond that inhibits the formation of defects and immobilizes anions near the surface.

As a result, the performance and stability of the PSC is enhanced synchronously across a wide range of sizes. The researchers achieved a 24.8% photoelectric conversion efficiency (PCE) for a 0.16 cm² cell and 18.1% PCE for a 228 cm² solar module, which is comparable to the best-performing solar module in its class.

What's more, a series of accelerated aging tests showed that the researchers' gas phase treated solar module had an intrinsic T80 lifetime (the time when efficiency is maintained at 80%) of 43,000 ± 9,000 hours, equivalent to more than four years of continuous operation at 30°C.

The extraction, degradation and activation energy of the gas phase treated solar module is 0.61 eV, which is comparable to the most stable battery reported in the literature, narrowing the stability gap between the battery and the module. The results pave the way for obtaining uniform and stable perovskite films for efficient and stable solar modules or other perovskite-based devices.

Link: https://www.science.org/doi/10.1126/science.adn9453