Lifetime over 10000 hours for organic solar cells with Ir/IrO_x electron-transporting layer

Area of Science:

• Materials Science
• Energy Science
• Nanotechnology

Background:

• Organic solar cells (OSCs) face stability challenges hindering widespread adoption.
• Efficient electron-transporting layers (ETLs) are crucial for OSC performance and longevity.

Purpose of the Study:

• To investigate the potential of an Iridium/Iridium oxide (Ir/IrO_x) ETL for enhancing OSC stability and performance.
• To compare the stability of Ir/IrO_x-based OSCs against traditional Zinc Oxide (ZnO)-based devices.

Main Methods:

• Fabrication of OSCs utilizing an Ir/IrO_x ETL.
• Evaluation of device performance and stability under shelf storage, thermal aging, and maximum power point tracking (MPPT).
• Analysis of photoactive layer morphology and charge dynamics in aged devices.

Main Results:

• Ir/IrO_x ETL-based OSCs demonstrated significantly improved operational stability, with T₈₀ of 56,696 hours (shelf), T₇₀ of 13,920 hours (thermal), and T₈₀ of 1,058 hours (MPPT).
• The enhanced stability is attributed to the optimized molecular distribution within the photoactive layer and the absence of photocatalysis.
• Ir/IrO_x ETL facilitated improved charge extraction and suppressed charge recombination in aged devices.

Conclusions:

• The Ir/IrO_x ETL is a promising material for developing highly stable organic solar cells.
• This work offers a viable solution to the critical stability issue in OSC technology.
• The findings support the use of Ir/IrO_x as a reliable ETL for next-generation solar energy devices.