Robust and stable dual-band electrochromic smart window with multicolor tunability

Area of Science:

• Materials Science
• Energy Science
• Optoelectronics

Background:

• Dual-band electrochromic smart windows (DESWs) can reduce building energy consumption by controlling visible (VIS) and near-infrared (NIR) light.
• Existing DESWs are limited to a single color switch (colorless to blue), restricting their applications.

Purpose of the Study:

• To develop a robust and stable DESW with multicolor conversion capabilities.
• To demonstrate independent control of VIS and NIR light transmittance using a single-component organic polymer.

Main Methods:

• Utilized polyaniline (PANI), a single-component organic polymer, for DESW fabrication.
• Investigated the progressive electrochemical reaction of PANI for electrochromic properties.
• Fabricated and tested a prototype PANI-based DESW device (10 × 5 cm²).

Main Results:

• Achieved multicolor electrochromism with transitions from yellow to green to black.
• Demonstrated efficient and independent control of VIS and NIR light transmittance.
• Reported significant optical modulation (65% at 633 nm, 59% at 1600 nm) and high coloration efficiency.
• Exhibited excellent cycling stability with minimal optical modulation loss after 10,000 cycles.

Conclusions:

• Polyaniline enables multicolor electrochromism in DESWs, overcoming the limitations of single-color systems.
• The developed PANI-based DESW offers independent modulation of sunlight and solar heat transmittance.
• This technology holds promise for advanced smart windows with enhanced energy efficiency and aesthetic versatility.