A Stretchable, Transparent, and Mechanically Robust Silver Nanowire-Polydimethylsiloxane Electrode for Electrochromic...

Area of Science:

• Materials Science
• Nanotechnology
• Device Engineering

Background:

• Flexible electrochromic devices are crucial for wearable technology.
• Indium tin oxide (ITO)-free substrates, particularly silver nanowire/poly(dimethylsiloxane) (AgNW/PDMS) films, are gaining interest.
• Challenges exist in achieving high transparency and low resistance due to weak AgNW-PDMS adhesion.

Purpose of the Study:

• To develop a novel stretchable AgNW/PDMS electrode with enhanced transparency and conductivity.
• To address the limitations of weak interfacial binding in AgNW/PDMS composites.
• To create a robust substrate for advanced flexible electrochromic devices.

Main Methods:

• Patterning pre-cured PDMS (PT-PDMS) using a stainless steel film template to create micron grooves and embedded structures.
• Fabricating stretchable AgNW/PT-PDMS electrodes via this novel patterning method.
• Evaluating electrode performance under mechanical stress (stretching, twisting, friction) and electrochromic cycling.

Main Results:

• The patterned AgNW/PT-PDMS electrode demonstrated high transparency and conductivity.
• Excellent mechanical robustness was observed, with minimal conductivity loss after 5000 stretching cycles, twisting, and 500 friction cycles (ΔR/R ≈ 16% and 27%).
• Increased stretching (10-80%) led to enhanced transmittance and initial conductivity increase, attributed to AgNW spreading and inter-nanowire contact within grooves.
• Electrochromic devices using these electrodes showed stable performance (transmittance contrast ~61% to ~57%) after 10,000 bending or 500 stretching cycles.

Conclusions:

• The proposed method effectively prepares transparent, stretchable electrodes with high conductivity and stability.
• Patterned PDMS serves as a promising strategy for overcoming interfacial challenges in AgNW/PDMS composites.
• This approach offers a viable solution for developing high-performance, mechanically robust electronic devices, particularly flexible electrochromic systems.