All-polymer bulk heterojuction solar cells with 4.8% efficiency achieved by solution processing from a co-solvent.

Area of Science:

• Materials Science
• Organic Electronics
• Renewable Energy

Background:

• All-polymer solar cells (APSCs) offer potential advantages like mechanical flexibility and low-cost manufacturing.
• Achieving high power conversion efficiency (PCE) in APSCs remains a key challenge.
• Current processing methods often limit the performance of the active layer.

Purpose of the Study:

• To investigate the impact of co-solvent processing on the performance of all-polymer solar cells.
• To achieve record power conversion efficiency in solution-processed APSCs.
• To establish co-solvent processing as a viable strategy for high-performance organic photovoltaics.

Main Methods:

• Fabrication of all-polymer solar cells using a co-solvent processing technique for the active layer.
• Characterization of photovoltaic properties, including power conversion efficiency, short-circuit current density, and external quantum efficiency.
• Analysis of the active layer morphology and charge transport dynamics influenced by co-solvent processing.

Main Results:

• Achieved a power conversion efficiency (PCE) of 4.8% in all-polymer solar cells.
• Recorded a short-circuit current density (Jsc) of 10.5 mA cm⁻² and an external quantum efficiency (EQE) of 61.3%.
• These results represent the highest reported values for all-polymer solar cells to date.

Conclusions:

• Solution processing of the active layer from a co-solvent is a critical strategy for enhancing APSC performance.
• Co-solvent processing significantly improves charge generation and transport, leading to higher efficiencies.
• This work demonstrates a promising pathway towards commercially viable, high-efficiency all-polymer solar cells.