Continuous In-Situ Polymerization of Complex-Based Films for High-Performance Electrochromic Devices

Area of Science:

• Materials Science
• Electrochemistry
• Polymer Chemistry

Background:

• High-performance electrochromic devices require uniform and stable electrochromic films on conductive layers.
• Developing convenient and feasible polymer film preparation technologies is crucial for advancing electrochromic applications.

Purpose of the Study:

• To demonstrate a continuous in situ polymerization method for preparing electrochromic films.
• To investigate the electrochromic properties and stability of the synthesized polymer films.

Main Methods:

• Continuous in situ polymerization via Schiff base condensation of a tetraamine Fe-based complex and organic di-/tri-aldehyde precursors.
• Coating the electrochromic film onto Indium Tin Oxide (ITO) glass.
• Characterization of film morphology, stability, and electrochemical properties.

Main Results:

• Uniform and stable electrochromic films were successfully coated on ITO glass.
• Film P1 exhibited two reversible redox processes, enabling two-step electrochromism (Fe(II)/Fe(III) and triphenylamine oxidation).
• Three stable color states (yellow, orange-red, blue) were achieved with fast response times (0.4–1.2 s) and high coloration efficiencies (241.5–352.9 cm²/C).

Conclusions:

• The continuous in situ polymerization method offers a feasible strategy for creating high-performance electrochromic polymer films.
• The developed films demonstrate excellent electrochromic performance suitable for advanced device applications.