Toward Enhancing Solar Cell Performance: An Effective and "Green" Additive.

Area of Science:

• Materials Science
• Organic Electronics
• Renewable Energy

Background:

• Polymer solar cells (PSCs) performance depends on photoactive layer morphology.
• Conjugated polymers and fullerene derivatives are key donor and acceptor materials.

Purpose of the Study:

• To investigate butylamine as a "greener" additive for optimizing PSC morphology.
• To understand the mechanism of morphology improvement in poly(3-hexylthiophene-2,5-diyl):phenyl-C61-butyric acid methyl ester (P3HT:PCBM) blends.

Main Methods:

• Utilized butylamine as an additive during the fabrication of P3HT:PCBM films.
• Employed atomic force microscopy (AFM) and X-ray photoelectron spectroscopy (XPS) for morphological analysis.
• Fabricated and tested PSC devices to evaluate performance enhancement.

Main Results:

• Butylamine facilitated vertical phase segregation, creating P3HT-rich top surfaces and PCBM-rich bottom layers.
• This optimized morphology led to enhanced charge extraction and improved fill factors.
• Power conversion efficiencies increased by 19.6-21.6% compared to devices without butylamine, reaching up to 4.61%.

Conclusions:

• Butylamine is an effective and "greener" additive for enhancing PSC performance.
• Differential affinity of additives towards donors and acceptors is crucial for morphology optimization.
• Findings support the development of large-area PSC fabrication with environmentally friendly additives.