Boosting Highly Efficient Hydrocarbon Solvent-Processed All-Polymer-Based Organic Solar Cells by Modulating Thin-Film...

Area of Science:

• Materials Science
• Renewable Energy
• Organic Electronics

Background:

• All-polymer organic solar cells (OSCs) are highly efficient but often rely on toxic halogenated solvents.
• Developing green processing methods is crucial for the sustainability of OSC technology.

Purpose of the Study:

• To compare the performance and morphology of all-polymer OSCs processed with toluene versus chloroform.
• To establish a new direction for low-toxicity solvent-processed OSCs with high efficiency.

Main Methods:

• Fabrication of PM6:PY-IT-based all-polymer devices using identical blend solutions and processing conditions, with only the solvent (chloroform vs. toluene) varied.
• Characterization of film morphology, crystallinity, charge transport, exciton recombination, and charge extraction.
• Device performance testing, including power conversion efficiency (PCE) and photostability.

Main Results:

• Toluene processing resulted in weaker film crystallinity compared to chloroform.
• Toluene-processed devices achieved a higher PCE of 15.51%, surpassing chloroform-processed devices (15.00%).
• Toluene enhanced charge transport, balanced charge mobility, suppressed exciton recombination, and improved charge extraction, leading to higher efficiency and slightly better photostability.

Conclusions:

• Toluene is a viable non-halogenated solvent for processing high-performance all-polymer OSCs.
• Morphology tuning by toluene significantly improves device efficiency and stability.
• This work paves the way for greener, high-efficiency polymer solar cell fabrication.