High-Efficiency Ternary Polymer Solar Cells with a Gradient-Blended Structure Fabricated by Sequential Deposition

Area of Science:

• Materials Science
• Organic Electronics
• Photovoltaics

Background:

• Optimizing active layer morphology is crucial for efficient charge separation and collection in polymer solar cells (PSCs).
• Ternary strategies and sequential deposition are key techniques for enhancing PSC performance.

Purpose of the Study:

• To combine ternary strategy and sequential deposition to optimize PSCs.
• To improve solar spectrum utilization, energy-level structure, and vertical phase separation.
• To enhance the power conversion efficiency (PCE) and stability of PSCs.

Main Methods:

• Utilized a ternary strategy combining donor and acceptor materials.
• Employed a sequential deposition process for film fabrication.
• Analyzed the gradient-blended distribution and carrier characteristics in the films.

Main Results:

• Achieved a gradient-blended distribution of donor and acceptor in sequential deposition-processed films.
• Demonstrated facilitated carrier characteristics in gradient-blended devices.
• PSC devices based on D18-Cl/Y6:ZY-4Cl reached over 18% power conversion efficiency (PCE).
• Observed synergistic improvements in open-circuit voltage (Voc), short-circuit current density (Jsc), and fill factor (FF).

Conclusions:

• The combined ternary strategy and sequential deposition offer a facile approach for fabricating high-performance PSCs.
• This method effectively enhances PCE and stability by optimizing morphology and energy levels.
• The gradient-blended morphology facilitates improved carrier transport and collection.