Nucleation Modification in Two-Step Slot-Die Coating Toward Efficient Large Scale Perovskite/Silicon Tandems Based on...

Area of Science:

• Materials Science
• Renewable Energy

Background:

• Vapor-solution two-step deposition is promising for perovskite/silicon tandem solar cells (TSCs).
• Scaling up TSC fabrication from spin-coating to slot-die methods faces challenges like residual PbI2 and voids in perovskite films.
• Achieving high power conversion efficiency (PCE) in large-area TSCs is crucial for mass production.

Purpose of the Study:

• To address challenges in large-area perovskite film fabrication for TSCs.
• To improve perovskite crystal growth and reduce voids in films deposited on textured silicon substrates.
• To enable efficient and scalable manufacturing of perovskite/silicon TSCs.

Main Methods:

• Utilized sodium 2,5-difluorobenzoate (2,5-NaDPA) additive during perovskite film deposition.
• Investigated the effect of 2,5-NaDPA on nucleation energy barriers and crystal growth.
• Employed slot-die coating for large-area perovskite film fabrication on textured silicon substrates.

Main Results:

• 2,5-NaDPA reduced nucleation energy barrier differences, promoting larger perovskite grain sizes.
• Voids in large-area perovskite films were significantly reduced.
• A fully textured perovskite/silicon tandem device with an effective area of 19.9 cm² achieved a high PCE of 28.28%.

Conclusions:

• Sodium 2,5-difluorobenzoate is an effective additive for improving large-area perovskite film quality in TSCs.
• This method facilitates the commercial production of large-area, high-efficiency perovskite/silicon tandem solar cells.
• The study presents a viable pathway for scalable manufacturing of advanced solar cell technologies.