Indene-C(60) bisadduct: a new acceptor for high-performance polymer solar cells

Area of Science:

• Materials Science
• Organic Electronics
• Photovoltaics

Background:

• Polymer solar cells (PSCs) utilize a blend of conjugated polymer donors and fullerene derivative acceptors.
• Poly(3-hexylthiophene) (P3HT) and [6,6]-phenyl-C-61-butyric acid methyl ester (PCBM) are common P3HT-based PSC materials.
• PCBM's low LUMO level restricts the open-circuit voltage (V(oc)) of P3HT:PCBM solar cells to approximately 0.6 V.

Purpose of the Study:

• To synthesize and evaluate a novel soluble fullerene derivative, indene-C(60) bisadduct (ICBA), as an alternative acceptor material for PSCs.
• To improve the V(oc) and power conversion efficiency (PCE) of P3HT-based PSCs by employing ICBA.

Main Methods:

• Synthesis of the indene-C(60) bisadduct (ICBA) fullerene derivative.
• Fabrication of PSC devices using P3HT as the donor and either ICBA or PCBM as the acceptor.
• Characterization of PSC performance under AM1.5, 100 mW/cm(2) illumination, including V(oc) and PCE measurements.

Main Results:

• ICBA possesses a 0.17 eV higher LUMO energy level compared to PCBM.
• PSCs fabricated with P3HT:ICBA exhibited a significantly higher V(oc) of 0.84 V and PCE of 5.44%.
• PSCs fabricated with P3HT:PCBM showed a V(oc) of 0.58 V and PCE of 3.88% under identical conditions.

Conclusions:

• ICBA serves as a high-performance acceptor material for P3HT-based PSCs.
• The higher LUMO level of ICBA effectively increases the V(oc) of PSCs.
• ICBA is a promising alternative acceptor for developing high-efficiency polymer solar cells.