High-Performance Polymer Solar Cells with PCE of 10.42% via Al-Doped ZnO Cathode Interlayer

Area of Science:

• Materials Science
• Organic Electronics
• Photovoltaics

Background:

• Polymer solar cells (PSCs) offer a promising alternative for renewable energy generation.
• Efficient charge extraction at the cathode is crucial for optimizing PSC performance.
• Developing low-temperature processed cathode interlayers is essential for cost-effective manufacturing and flexible device fabrication.

Purpose of the Study:

• To investigate the efficacy of low-temperature processed aluminum-doped zinc oxide (AZO) as a cathode interlayer in high-performance polymer solar cells.
• To evaluate the impact of AZO thickness on device performance.
• To demonstrate the feasibility of using AZO interlayers in flexible PSCs.

Main Methods:

• Fabrication of polymer solar cells utilizing PTB7-Th:PC71 BM active layers.
• Incorporation of aluminum-doped zinc oxide (AZO) as a cathode interlayer, processed at low temperatures.
• Characterization of device performance, including power conversion efficiency (PCE) and stability.
• Fabrication and testing of flexible devices on poly(ethylene terephthalate)/indium tin oxide substrates.

Main Results:

• Achieved a power conversion efficiency (PCE) of 10.42% for rigid polymer solar cells with AZO interlayers, independent of AZO thickness.
• Obtained a PCE of 8.93% for flexible polymer solar cells.
• Demonstrated well-distributed efficiency and good device stability in the fabricated flexible devices.

Conclusions:

• Low-temperature processed AZO is an effective cathode interlayer for high-performance polymer solar cells.
• AZO enables efficient charge extraction, leading to high PCE values.
• The developed AZO-based technology is suitable for fabricating stable and efficient flexible polymer solar cells.