High-Performance Inverted Perovskite Solar Devices Enabled by a Polyfullerene Electron Transporting Material

Area of Science:

• Materials Science
• Renewable Energy
• Photovoltaics

Background:

• Electron transporting materials (ETMs) are crucial for perovskite solar cell (PSC) performance and stability.
• The common ETM, PCBM, suffers from aggregation and migration, limiting device longevity.

Purpose of the Study:

• To develop a new, stable ETM for inverted PSCs.
• To address the limitations of conventional fullerene ETMs like PCBM.

Main Methods:

• Polymerization of C60 fullerene with an aromatic linker to create polyfullerene (PFBS-C12).
• Fabrication and characterization of PSCs using the novel PFBS-C12 ETM.
• Stability testing under light soaking conditions.

Main Results:

• The developed polyfullerene (PFBS-C12) retains favorable optoelectronic properties.
• Blade-coated PSCs with PFBS-C12 achieved 23.2% power conversion efficiency.
• Devices maintained 96% of initial efficiency after >1300 hours of light soaking.
• A 53.6 cm² perovskite mini-module demonstrated 18.9% aperture efficiency.

Conclusions:

• PFBS-C12 offers a promising alternative to PCBM for stable PSCs.
• This work presents a new strategy for designing robust ETMs for efficient perovskite solar devices.