Sublimated Cyanoacetamide-Driven Surface Recrystallization for Spray-Coated Wide-Bandgap Perovskite Solar Cells

Area of Science:

• Materials Science
• Renewable Energy
• Photovoltaics

Background:

• Spray-coated wide-bandgap perovskite solar cells are promising for tandem applications due to low cost and scalability.
• Increased layers in spray-coating lead to surface roughness and defects, hindering performance.

Purpose of the Study:

• To improve the quality and performance of spray-coated wide-bandgap perovskite solar cells.
• To address surface roughness and defect formation in multi-layered perovskite films.

Main Methods:

• Utilized N,N-dimethyl-2-cyanoacetamide (DMCA), a solid-phase compound, to induce lattice reorganization.
• DMCA intercalates into the perovskite lattice, forming a liquid intermediate state, followed by heating for lattice reconstruction.
• Optimized wide-bandgap (1.67 eV) perovskite solar cells using the spray-coating method.

Main Results:

• DMCA treatment significantly reduced surface roughness and defect density in perovskite films.
• Achieved a record power conversion efficiency (PCE) of 22.56% with a high open-circuit voltage of 1.23 V.
• Unencapsulated devices demonstrated excellent operational stability, maintaining efficiency over 1200 hours of continuous illumination.

Conclusions:

• DMCA is an effective additive for improving the quality and performance of spray-coated perovskite solar cells.
• The developed method offers a pathway for highly efficient and stable perovskite solar cells for future energy applications.
• Spray-coated perovskite solar cells treated with DMCA show potential for commercial viability in tandem solar cell technologies.