Photoresponsive Smart Coloration Electrochromic Supercapacitor

Area of Science:

• Materials Science
• Energy Storage
• Electrochemistry

Background:

• Electrochromic devices are used in energy-saving applications but lack smart coloration and energy storage.
• There is a need for advanced electrochromic devices that respond to light intensity and function as rechargeable energy storage systems.

Purpose of the Study:

• To develop a photoresponsive electrochromic supercapacitor with smart coloration and energy storage capabilities.
• To investigate the performance, durability, and photoresponsive properties of the novel composite electrode.

Main Methods:

• Fabrication of a composite electrode using cellulose nanofiber, silver nanowire, reduced graphene oxide, and WO3.
• Integration of the electrode into an electrochromic supercapacitor device.
• Testing of coloration efficiency, electrochemical performance (capacitance, energy/power densities), cycle reliability, and mechanical durability.
• Integration with a solar sensor for photoresponsive coloration.

Main Results:

• The developed device demonstrated a high coloration efficiency (64.8 cm²/C) and excellent electrochemical performance (specific capacitance of 406.0 F/g, energy densities of 40.6–47.8 Wh/kg).
• The electrochromic supercapacitor retained 75.0% of its coloration efficiency and 94.1% of its electrochemical performance after 10,000 cycles, indicating high reliability.
• Cyclic fatigue tests confirmed the device's mechanical durability, making it suitable for wearable electronics.
• The integrated system exhibited photoresponsive coloration, with transmittance changing in response to varying light intensity.

Conclusions:

• A novel photoresponsive electrochromic supercapacitor was successfully developed, combining smart coloration with reliable energy storage.
• The device exhibits outstanding electrochemical and electrochromic performance, along with excellent long-term stability and mechanical durability.
• This technology holds significant potential for applications in smart windows, energy-saving displays, and wearable electronic devices.