Achieving over 9.8% Efficiency in Nonfullerene Polymer Solar Cells by Environmentally Friendly Solvent Processing

Area of Science:

• Materials Science
• Organic Electronics
• Renewable Energy

Background:

• Most high-efficiency polymer solar cells (PSCs) rely on harmful halogenated solvents.
• Developing eco-friendly processing methods is crucial for PSC industrialization and environmental safety.

Purpose of the Study:

• To introduce a novel conjugated polymer, PBDB-TS, for efficient PSCs processed using environmentally friendly solvents.
• To demonstrate the potential of PBDB-TS as a key component in sustainable solar cell technology.

Main Methods:

• Synthesis of a new alkylthio chain-based conjugated polymer, PBDB-TS.
• Fabrication of PSC devices using PBDB-TS as the donor material with o-xylene and N-methylpyrrolidone as processing solvents.
• Characterization of film morphology, charge transport properties, and device performance.

Main Results:

• PBDB-TS exhibits a low-lying HOMO energy level (-5.42 eV) and good solubility in non-halogenated solvents.
• PSC devices processed with o-xylene achieved a high power conversion efficiency (PCE) of 9.85%.
• The PCE of devices processed with eco-friendly solvents exceeded that of devices processed with halogenated solvents (9.65%).

Conclusions:

• PBDB-TS is a promising donor material for developing high-performance, environmentally friendly PSCs.
• The study validates the feasibility of using non-halogenated solvents for efficient PSC fabrication.
• This work contributes to the advancement of sustainable organic electronics.