Solvent Retention and Crack Evolution in Dropcast PEDOT:PSS and Dependence on Surface Wetting

Area of Science:

• Materials Science
• Polymer Chemistry
• Surface Science

Background:

• Drying of nanocolloidal polymers involves complex phenomena like surface tension and evaporation.
• Poly(3,4-ethylenedioxythiophene):poly(styrene sulfonate) (PEDOT:PSS) is a widely used conductive polymer.
• Understanding drying-induced cracking is crucial for film quality.

Purpose of the Study:

• To investigate the drying dynamics of PEDOT:PSS films.
• To determine the influence of substrate wetting on cracking and morphology.
• To explore methods for controlling film properties.

Main Methods:

• Observation of PEDOT:PSS drying through distinct regimes.
• Analysis of cracking patterns (annular or radial).
• Correlation of wetting properties with morphology and solvent retention.

Main Results:

• PEDOT:PSS drying exhibits two regimes characterized by specific cracking patterns.
• Substrate wetting significantly mediates cracking dynamics and solvent retention.
• Morphological changes are directly linked to cracking behavior.

Conclusions:

• Wetting-dependent effects provide a pathway to control PEDOT:PSS film morphology.
• Understanding wetting is key to managing solvent retention and reducing film cracking.
• Substrate choice is a critical, yet often overlooked, factor in colloidal material studies.