High-efficiency inverted polymer solar cells with transparent and work-function tunable MoO(3)-Al composite film as...

Area of Science:

• Materials Science
• Organic Electronics
• Photovoltaics

Background:

• Polymer solar cells (PSCs) offer a promising alternative for renewable energy generation.
• Optimizing interfacial layers is crucial for enhancing PSC efficiency and stability.
• Previous cathode buffer layers often present fabrication challenges or limited tunability.

Purpose of the Study:

• To develop and demonstrate high-efficiency inverted polymer solar cells.
• To investigate the use of a novel MoO(3)-Al composite film as a cathode buffer layer.
• To optimize interfacial properties for reduced recombination and improved photovoltaic performance.

Main Methods:

• Fabrication of inverted polymer solar cells using a PCDTBT:PC(70)BM blend.
• Implementation of a MoO(3)-Al composite film as the cathode buffer layer.
• Tuning the work function of the MoO(3)-Al layer by adjusting aluminum content.

Main Results:

• Achieved a power conversion efficiency (PCE) of 6.77%.
• Recorded an open-circuit voltage (V(OC)) of 0.88 V, a short-circuit current density (J(SC)) of 10.88 mA cm(-2), and a fill factor (FF) of 70.7%.
• Demonstrated that MoO(3)-Al composite films possess tunable work functions and high transparency, optimizing cathode buffer layer/BHJ interfaces.

Conclusions:

• The MoO(3)-Al composite cathode buffer layer effectively reduces recombination loss.
• This approach simplifies device fabrication, paving the way for cost-effective, large-scale applications.
• The tunable work function of the composite film is key to enhancing photovoltaic performance in PSCs.