Performance improvement of P3HT nanowire-based organic solar cells by interfacial morphology engineering

Area of Science:

• Organic electronics
• Materials science
• Nanotechnology

Background:

• Poly (3-hexylthiophene-2,5-diyl) nanowires (P3HT) are crucial for organic electronics like transistors and photovoltaics.
• Understanding charge transport and morphology is key to optimizing device performance.

Purpose of the Study:

• To investigate the optoelectronic properties of P3HT nanowires with polymer backbones parallel to the nanowire axis.
• To explore the effect of 1,8-diiodooctane (DIO) additive on P3HT nanowire bundle separation and its impact on photovoltaic performance.

Main Methods:

• Fabrication of P3HT nanowires and their bundling.
• Utilizing 1,8-diiodooctane (DIO) as an additive to separate nanowire bundles.
• Atomic force microscopy (AFM) for visualizing bundle separation.
• Electrochemical impedance spectroscopy (EIS) for evaluating charge transfer mechanisms.

Main Results:

• P3HT nanowires naturally form bundles due to van der Waals interactions.
• DIO additive effectively separated these bundles, which was confirmed by AFM.
• Electrochemical impedance spectroscopy revealed a correlation between effective lifetime and DIO ratio.
• Short-circuit current density (Jsc) increased to 10.74 mA cm⁻² after bundle separation.

Conclusions:

• Bundle separation of P3HT nanowires using DIO is a promising strategy for enhancing charge carrier transport.
• The optimized morphology improves device performance, particularly the short-circuit current density in photovoltaic applications.
• Findings suggest a pathway for improving charge transport by controlling nanowire morphology.