Low-Cost Fabrication of Efficient Perovskite Photovoltaics Using Low-Purity Lead Iodide via Powder Engineering

Area of Science:

• Materials Science
• Renewable Energy
• Photovoltaics

Background:

• Low-cost fabrication is crucial for commercializing perovskite solar cells (PSCs).
• Previous efforts focused on processing methods and device structures, with limited attention to precursor costs.
• Utilizing low-purity precursors presents a significant challenge for efficient PSCs.

Purpose of the Study:

• To develop a low-cost fabrication strategy for efficient PSCs using inexpensive, low-purity lead iodide (PbI2).
• To demonstrate the effectiveness of powder engineering for purifying low-purity PbI2 and producing high-quality FAPbI3.
• To evaluate the performance and stability of PSCs fabricated with the novel low-cost precursor method.

Main Methods:

• Powder engineering of low-purity PbI2 blended with formamidinium iodide.
• Inverse temperature crystallization and solvent washing to reduce impurities and form high-quality FAPbI3 powders.
• Fabrication and characterization of PSC devices and a 5 cm x 5 cm solar minimodule.

Main Results:

• Achieved a champion power conversion efficiency (PCE) of 23.9% for PSCs using low-purity PbI2.
• Demonstrated excellent stability, retaining ~95% of initial PCE after ~400 hours of unencapsulated storage.
• Successfully scaled up fabrication to a 5 cm x 5 cm solar minimodule with 19.5% efficiency.

Conclusions:

• Powder engineering effectively purifies low-purity PbI2, enabling low-cost, high-efficiency PSC fabrication.
• This approach offers a viable economic strategy for the commercialization of PSC technology.
• The developed method significantly reduces precursor costs without compromising device performance or stability.