Low-Temperature UVO-Sintered ZnO/SnO2 as Robust Cathode Buffer Layer for Ternary Organic Solar Cells
Zhijun Zou1, Fen Li1, Jing Fang1
1Key Laboratory of Hunan Province on Information Photonics and Freespace Optical Communications, College of Physics and Electronics, Hunan Institute of Science and Technology, Yueyang 414006, China.
Nanomaterials (Basel, Switzerland)
|September 23, 2022
Summary
A novel bilayer cathode buffer layer (CBL) using UV-ozone sintered ZnO nanoparticles and SnO2 significantly enhances organic solar cell (OSC) performance and stability. This low-temperature process offers great potential for flexible OSC applications.
Area of Science:
- Materials Science
- Organic Electronics
- Photovoltaics
Background:
- The cathode buffer layer (CBL) is critical for efficient organic solar cells (OSCs).
- Developing high-quality CBLs with simple, reliable, low-temperature processes remains a challenge.
Purpose of the Study:
- To prepare a robust bilayer CBL using ZnO nanoparticles (NPs) and sol-gel SnO2 via a low-temperature UV-ozone (UVO) sintering process.
- To investigate the impact of this novel CBL on the performance and stability of ternary OSCs.
Main Methods:
- Fabrication of a bilayer CBL comprising UVO-sintered ZnO NPs and sol-gel SnO2.
- Integration of the UVO-ZnO/SnO2 CBL into ternary OSCs (PTB7-Th:PCDTBT:PC70BM).
- Characterization of CBL properties (compactness, flatness, transmittance, electron mobility) and device performance (PCE, stability).
Main Results:
- The SnO2 layer effectively filled pores and cracks in the ZnO NP film, enhancing CBL compactness and reducing defects.
- The UVO-ZnO/SnO2 CBL exhibited improved transmittance and increased electron mobility, facilitating electron extraction.
- Devices with the UVO-ZnO/SnO2 CBL achieved a peak power conversion efficiency (PCE) of 10.56%, outperforming control devices.
- Significantly enhanced device stability was observed, with 60% of initial PCE retained after 30 days in air.
Conclusions:
- The UVO-sintered ZnO/SnO2 bilayer structure is an effective and robust CBL for high-performance OSCs.
- The low-temperature fabrication process makes this CBL suitable for flexible organic solar cell applications.
- This approach offers a promising strategy for advancing OSC technology.
