Solvent-Engineering-Assisted Ligand Exchange Strategy for High-Efficiency AgBiS₂ Quantum Dot Solar Cells

Area of Science:

• Materials Science
• Nanotechnology
• Renewable Energy

Background:

• Colloidal quantum dots (CQDs) require ligand exchange for effective solar cell fabrication.
• Water adsorption during ligand exchange creates defects, hindering device performance.
• Developing robust ligand exchange strategies is crucial for CQD-based optoelectronics.

Purpose of the Study:

• To develop a solvent-engineering-assisted ligand exchange strategy for silver bismuth disulfide (AgBiS2) CQDs.
• To improve ligand exchange efficiency and control surface chemistry.
• To enhance the performance and stability of AgBiS2 CQD solar cells.

Main Methods:

• Solvent-engineering-assisted ligand exchange applied to AgBiS2 CQDs.
• Fabrication and characterization of AgBiS2 CQD solar cells.
• Evaluation of power conversion efficiency (PCE) and long-term stability.

Main Results:

• Achieved a champion PCE of 8.95% for optimized AgBiS2 CQD solar cells.
• Demonstrated improved long-term stability of the photovoltaic devices.
• The developed strategy showed minimal performance variance across batches and over time.

Conclusions:

• Solvent engineering is critical for effective ligand exchange in CQDs.
• The new strategy enhances surface chemistry and device performance reproducibly.
• This work paves the way for high-performance, stable, and scalable CQD solar cells.