Perovskite solar cells based on screen-printed thin films.

Area of Science:

• Materials Science
• Renewable Energy
• Photovoltaics

Background:

• Perovskite solar cells (PSCs) offer advantages due to solution-processable precursors.
• Current deposition methods for PSCs include spin coating, blade coating, spray coating, inkjet printing, and slot-die printing.
• There is a need for scalable and cost-effective deposition techniques for PSCs.

Purpose of the Study:

• To introduce screen-printing as a viable deposition method for perovskite thin films.
• To develop a stable, viscosity-adjustable perovskite ink suitable for screen-printing.
• To demonstrate control over film properties and device performance using screen-printing.

Main Methods:

• Developed a stable perovskite ink with adjustable viscosity (40-44,000 cP) using a methylammonium acetate ionic liquid solvent.
• Employed screen-printing to deposit perovskite thin films with controlled thickness (120-1200 nm) and area (0.5x0.5 cm² to 5x5 cm²).
• Evaluated printing rates (>20 cm/s) and ink utilization (near 100%).

Main Results:

• Achieved high power conversion efficiencies of 20.52% (0.05 cm²) and 18.12% (1 cm²) for screen-printed films, outperforming spin-coated films.
• Demonstrated fully screen-printed devices with efficiencies of 14.98% (0.05 cm²), 13.53% (1 cm²), and 11.80% (16.37 cm²).
• Screen-printed devices retained 96.75% of initial efficiency after 300 hours of operation.

Conclusions:

• Screen-printing is a highly effective and scalable method for fabricating high-efficiency perovskite solar cells.
• The developed perovskite ink and screen-printing process allow for fabrication in ambient air, irrespective of humidity.
• This advancement holds significant potential for the low-cost, large-scale manufacturing of perovskite photovoltaic devices.