Sputtering Flexible VO₂ Films for Effective Thermal Modulation

Area of Science:

• Materials Science
• Nanotechnology
• Energy

Background:

• Flexible thermochromic vanadium dioxide (VO₂) films offer significant advantages over rigid counterparts for large-scale applications.
• Fabricating high-performance flexible VO₂ films for smart windows remains a significant challenge, limiting research and development.

Purpose of the Study:

• To design and fabricate a flexible VO₂-based film with superior optical properties and extended durability for smart window applications.
• To develop a facile fabrication strategy for flexible VO₂ films suitable for direct attachment to glass.

Main Methods:

• Fabrication of a flexible ITO/VO₂/ITO (IVI) film on a transparent polyimide substrate.
• Characterization of the optical properties, including luminous transmittance (T_lum) and solar modulation ability (ΔT_sol).
• Evaluation of thermal emissivity (ε_T) and film durability.

Main Results:

• The flexible IVI film demonstrated enhanced luminous transmittance and solar modulation ability (15% and 68% increase, respectively, compared to VO₂ single layer).
• Reduced thermal emissivity (50.7% decrease compared to VO₂ single layer) was achieved.
• The fabricated film exhibited superior durability compared to existing flexible VO₂ structures.

Conclusions:

• The developed flexible IVI film shows excellent comprehensive performance, making it highly suitable for practical smart window applications.
• This work presents a novel and facile method for fabricating flexible VO₂ films, expanding their potential use in various coatings and devices.