High-clarity multifunctional Cu/Ni transparent films for efficient electromagnetic interference shielding

Area of Science:

• Materials Science
• Nanotechnology
• Optoelectronics

Background:

• Transparent conductive materials require high optical transmittance, electromagnetic interference (EMI) shielding, and environmental stability.
• Existing materials face challenges in simultaneously meeting these performance metrics.

Purpose of the Study:

• To develop a multifunctional transparent conductive mesh with optimized optical and electromagnetic properties.
• To investigate the impact of structural design on material performance.

Main Methods:

• Fabrication of a hexagonal-Voronoi composite metal mesh (HV-CMM) by integrating hexagonal and Voronoi structures.
• Tuning Voronoi feature size to optimize optical and electromagnetic characteristics.
• Characterization of optical transmittance, haze, EMI shielding effectiveness, electrothermal response, and environmental stability.

Main Results:

• HV-CMM achieved 78-83% optical transmittance and low haze (4.5-4.8%).
• Demonstrated average EMI shielding effectiveness of 38.5 dB (1-18 GHz) and rapid electrothermal response (143 °C in 150 s).
• Ni passivation improved environmental stability, reducing sheet resistance variation to 42.4% under harsh conditions.

Conclusions:

• The HV-CMM structure effectively suppresses diffraction, enhancing visual uniformity.
• Structure-material co-design offers a promising route for multifunctional transparent conductive meshes.
• Potential applications include optical windows, defogging/deicing systems, and electromagnetic protection.