Iodide manipulation using zinc additives for efficient perovskite solar minimodules

Area of Science:

• Materials Science
• Photovoltaics
• Solid-State Chemistry

Background:

• Interstitial iodides are a primary limitation in perovskite solar cell efficiency and stability.
• These defects form during various processing stages, accelerating device degradation.

Purpose of the Study:

• To investigate the use of zinc trifluoromethane sulfonate (Zn(OOSCF3)2) as an additive to control iodide defects in perovskite solar cells.
• To improve the efficiency and stability of perovskite films and devices.

Main Methods:

• Incorporation of zinc trifluoromethane sulfonate into perovskite precursor solutions.
• Analysis of iodide defect formation and suppression mechanisms.
• Characterization of perovskite film properties, including photoluminescence quantum efficiency and trap density.
• Fabrication and testing of large-area perovskite minimodules using blade-coating.

Main Results:

• Zinc trifluoromethane sulfonate effectively suppresses molecular iodine formation and precipitates excess iodide.
• Perovskite films exhibit improved photoluminescence quantum efficiency and reduced deep trap density.
• Zinc additives facilitate uniform film formation on large-area substrates.
• Certified power conversion efficiencies of 19.60% and 19.21% achieved for 84 cm2 and 108 cm2 minimodules, respectively.

Conclusions:

• Zinc trifluoromethane sulfonate is a promising additive for controlling iodide defects in perovskite solar cells.
• This approach leads to enhanced film quality and improved device performance, particularly for large-area applications.
• The study demonstrates a viable strategy for achieving high-efficiency, stable perovskite solar minimodules.