Electrically Sorted Single-Walled Carbon Nanotubes-Based Electron Transporting Layers for Perovskite Solar Cells

Area of Science:

• Materials Science
• Renewable Energy
• Nanotechnology

Background:

• Single-walled carbon nanotubes (SWCNTs) are incorporated into perovskite solar cells (PSCs) to improve photovoltaic performance.
• The specific roles of different electrical types of SWCNTs within the electron transporting layer (ETL) of PSCs remain unclear.

Purpose of the Study:

• To investigate the influence of semiconducting (s-SWCNTs) and metallic (m-SWCNTs) on the performance of PSCs.
• To elucidate the fundamental mechanisms by which different SWCNT electrical types affect electron extraction and transport in PSCs.

Main Methods:

• Preparation of distinct semiconducting and metallic SWCNT families.
• Integration of these SWCNTs into TiO2 photoelectrodes of PSCs.
• Utilized experimental and theoretical studies to analyze device performance and charge dynamics.

Main Results:

• PSCs incorporating a mixture of s-SWCNTs and m-SWCNTs (2:1 w/w) achieved a peak power conversion efficiency of 19.35%.
• This efficiency is significantly higher than the control cell's efficiency of 17.04%.
• Demonstrated that s-SWCNTs are crucial for efficient electron extraction and transport, while m-SWCNTs enhance overall electrode conductivity.

Conclusions:

• The electrical type of SWCNTs critically influences the photovoltaic performance of PSCs.
• A synergistic combination of s-SWCNTs and m-SWCNTs optimizes both electron transport and electrode conductivity, leading to enhanced device efficiency.
• This work provides fundamental insights into SWCNT-based electron transporting layers for advanced solar cell applications.