Ligand-Assisted Coupling Manipulation for Efficient and Stable FAPbI₃ Colloidal Quantum Dot Solar Cells

Area of Science:

• Materials Science
• Nanotechnology
• Photovoltaics

Background:

• Emerging perovskite quantum dots (QDs) require surface understanding for device applications.
• Hybrid formamidinium lead iodide (FAPbI3) QDs offer stability and near-infrared absorption but face challenges in surface ligand modulation for conductive arrays.
• Efficient charge transport is crucial for fabricating high-quality QD arrays for photovoltaic devices.

Purpose of the Study:

• To develop a facile surface reconfiguration methodology for FAPbI3 QDs.
• To modulate the surface and electronic coupling of FAPbI3 QDs.
• To enhance charge transport for improved QD arrays and photovoltaic devices.

Main Methods:

• Utilized an ionic liquid, formamidine thiocyanate, for surface reconfiguration.
• Developed a method to modulate surface ligands and electronic coupling in FAPbI3 QDs.
• Fabricated high-quality QD arrays and photovoltaic devices using the modified QDs.

Main Results:

• Achieved a record power conversion efficiency approaching 15% for FAPbI3 QD solar cells.
• Demonstrated enhanced charge transport through surface manipulation.
• The fabricated solar cells retained over 80% of their initial efficiency after 600 hours of ambient aging.

Conclusions:

• The developed surface reconfiguration methodology effectively enhances charge transport in FAPbI3 QDs.
• This approach enables the fabrication of high-performance and stable perovskite quantum dot solar cells.
• The findings pave the way for advanced applications of FAPbI3 QDs in photovoltaics.