Interfacial Crosslinking for Efficient and Stable Planar TiO2 Perovskite Solar Cells
Linrui Duan1, Siyu Liu1, Xiaobing Wang1
1Institute of Photoelectronic Thin Film Devices and Technology, State Key Laboratory of Photovoltaic Materials and Cells, Tianjin Key Laboratory of Efficient Solar Energy Utilization, Ministry of Education Engineering Research Center of Thin Film Photoelectronic Technology, Nankai University, Tianjin, 300350, China.
Summary
Researchers enhanced perovskite solar cell (PSC) performance by modifying the interface between the electron transport layer (ETL) and the perovskite layer. This modification improved power conversion efficiency (PCE) and device stability.
Area of Science:
- Materials Science
- Renewable Energy
- Photovoltaics
Background:
- The interface between the electron transport layer (ETL) and the perovskite layer is critical for the efficiency and stability of perovskite solar cells (PSCs).
- Chemical bath deposited (CBD) titanium oxide (TiO2) is a common ETL material, but interface engineering is needed for optimal performance.
Purpose of the Study:
- To investigate the effect of multi-functional potassium trifluoromethyl sulfonate (SK) on the TiO2/perovskite interface in n-i-p type PSCs.
- To improve the power conversion efficiency (PCE) and operational stability of PSCs by optimizing ETL/perovskite interface adhesion and reducing defects.
Main Methods:
- Modification of the TiO2 ETL/perovskite interface using potassium trifluoromethyl sulfonate (SK).
- Structural and elemental analyses to understand the crosslinking mechanism.
- Fabrication and characterization of PSC devices to evaluate PCE and stability.
Main Results:
- Potassium trifluoromethyl sulfonate acted as a crosslinker, enhancing adhesion between TiO2 ETL and the perovskite layer via strong bonding.
- Interface defects were reduced, and carrier recombination was suppressed, leading to improved device performance.
- A champion PCE of 25.22% and a fill factor (FF) of approximately 85% were achieved, the highest for PSCs with CBD TiO2.
- Unencapsulated devices retained 81.3% of their initial PCE after 1000 hours of operation.
Conclusions:
- The multi-functional SK modifier effectively enhances the TiO2/perovskite interface in PSCs.
- Interface engineering with SK leads to significant improvements in both PCE and long-term stability.
- This approach represents a promising strategy for developing high-performance and durable perovskite solar cells.
