Understanding the Microstructure Formation of Polymer Films by Spontaneous Solution Spreading Coating with a...

Area of Science:

• Materials Science
• Organic Electronics
• Polymer Science

Background:

• Low-band gap polymer donors, like PBDB-T derivatives, are crucial for high-efficiency organic solar cells.
• Polymer aggregation significantly impacts device performance, but optimization is challenging.
• Developing efficient organic solar cells requires precise control over thin-film morphology.

Purpose of the Study:

• To introduce a robot-based high-throughput platform (HTP) for automated film preparation and characterization.
• To develop an analysis algorithm for morphology optimization and understanding physical principles.
• To provide a methodology for analyzing exciton coherence length in conjugated semiconductors.

Main Methods:

• Utilized a robot-based high-throughput platform (HTP) for automated film preparation via spontaneous film spreading (SFS).
• Employed automated UV/Vis and photoluminescence (PL) spectroscopy for thin-film characterization.
• Integrated Gaussian Process Regression with spectral modeling for microstructure analysis and morphology optimization.

Main Results:

• The platform successfully prepared PM6 films and acquired spectral data.
• The spectral modeling workflow quantitatively distinguished amorphous and ordered phases in the films.
• The study enabled assessment of amorphous versus ordered domain extension and exciton coherence length.

Conclusions:

• The developed HTP offers an efficient approach to optimize thin-film morphology in organic semiconductors.
• This methodology facilitates the analysis of exciton coherence length, crucial for device performance.
• The findings pave the way for optimizing exciton splitting in organic semiconductor layers through processing control.