Ternary Organic Solar Cells by Small Amount of Efficient Light Absorption Polymer PSEHTT as Third Component Materials

Area of Science:

• Materials Science
• Organic Electronics
• Photovoltaics

Background:

• Organic solar cells (OSCs) offer a promising alternative for renewable energy generation.
• Ternary systems can enhance OSC performance by broadening spectral absorption and optimizing morphology.
• Developing efficient and stable OSCs is crucial for commercial viability.

Purpose of the Study:

• To investigate the effect of incorporating a medium wavelength absorption polymer (PSEHTT) into a PM6:L8-BO binary system for ternary organic solar cells.
• To enhance the power conversion efficiency (PCE) and understand the underlying mechanisms.
• To explore PSEHTT as a hybrid donor material for high-performance ternary OSCs.

Main Methods:

• Fabrication of ternary organic solar cells (OSCs) using PM6:L8-BO blended with varying concentrations of PSEHTT.
• Characterization of the photovoltaic properties, including power conversion efficiency (PCE), short-circuit current density (JSC), open-circuit voltage (VOC), and fill factor (FF).
• Analysis of the optical properties, morphology, and energy levels (HOMO) of the active layer.

Main Results:

• The incorporation of a small amount of PSEHTT into the PM6:L8-BO binary system resulted in a power conversion efficiency (PCE) increase from 15.83% to 16.66%.
• Significant improvements in short-circuit current density (JSC) and open-circuit voltage (VOC) were observed, despite a slight reduction in fill factor (FF).
• PSEHTT demonstrated good compatibility with PM6, broad short-wavelength absorption, and a deeper HOMO energy level, contributing to improved photon collection and a broader optical bandgap.

Conclusions:

• The addition of low-concentration PSEHTT as a hybrid donor material effectively enhances ternary OSC performance.
• Optimized morphology, improved photon collection, and a broadened optical bandgap are key factors contributing to the enhanced PCE.
• This study presents an effective strategy for fabricating high-performance ternary OSCs.