Development of Electrochromic Devices, Based on Polymeric Gel, for Energy Saving Applications

Area of Science:

• Materials Science
• Electrochemistry
• Energy Technology

Background:

• Electrochromic devices offer tunable optical properties for energy-saving applications.
• Developing efficient and stable electrochromic materials is crucial for widespread adoption.
• Existing technologies require optimization for performance across visible and near-infrared spectra.

Purpose of the Study:

• To implement and characterize a novel electrochromic device for energy-saving applications.
• To evaluate the electrochromic performance of a system based on ethyl viologen and ferrocene derivatives.
• To assess the device's optical and electrochemical properties for potential use in buildings.

Main Methods:

• Fabrication of a 10 cm × 10 cm electrochromic device using ethyl viologen diperchlorate, 1,1'-diethyl ferrocene, and propylene carbonate.
• Incorporation of a polymeric system (Bisphenol-A glycerolate diacrylate and Irgacure 651) for device stability.
• Utilizing lithography for spacer pattern creation and micro-Raman spectroscopy for material confirmation.
• Electrochemical and optical transmittance measurements across visible and near-infrared regions.

Main Results:

• The device exhibited reversible electrochromic behavior with significant transmittance modulation.
• At 400 nm, transmittance changed from 59.6% to 0.48%; at 606 nm, from 84.58% to 1.01%.
• Near-infrared performance showed transmittance changes from 74.3% to 23.7% at 890 nm and 83.21% to 1.58% at 1165 nm.
• High contrast ratio (CCR%) and excellent color efficiency (CE) were observed, with CE values up to 420.1 cm²/C in the NIR region.

Conclusions:

• The developed electrochromic device demonstrates promising performance for energy-saving applications.
• Its ability to modulate visible and NIR light makes it suitable for smart windows in buildings.
• The system shows excellent electrochromic properties and stability, warranting further investigation.