Vertical Gold Nanowires Stretchable Electrochemical Electrodes

Area of Science:

• Materials Science
• Nanotechnology
• Electrochemistry

Background:

• Conventional electrodes (gold, glassy carbon) are rigid and planar, limiting integration with soft biological tissues for wearable or implantable electronics.
• Seamless integration of electrochemical sensors with curvilinear biological tissues remains a significant challenge for real-time biodiagnostics.

Purpose of the Study:

• To develop intrinsically stretchable electrochemical electrodes using vertically aligned gold nanowires (v-AuNWs).
• To evaluate the electrochemical performance of v-AuNWs electrodes for biosensing applications under strain.
• To demonstrate the potential of v-AuNWs as a next-generation sensing platform for conformally integrated in vivo biodiagnostics.

Main Methods:

• Fabrication of vertically aligned gold nanowires (v-AuNWs) with an enokitake-like structure via wet chemistry.
• Characterization of v-AuNWs electrode structure and interfacial bonding forces with elastomers.
• Electrochemical performance evaluation (detection limit, linear range, sensitivity) using chronoamperometry for hydrogen peroxide (H2O2) detection at 20% strain.

Main Results:

• v-AuNWs electrodes exhibit an enokitake-like structure with nanoparticle heads and nanowire tails.
• Stronger nanowire-elastomer bonding prevents interfacial delamination under strain, ensuring stretchability.
• Achieved a detection limit of 80 μM for H2O2 with a linear range of 0.2-10.4 mM at 20% strain, demonstrating high sensitivity.

Conclusions:

• v-AuNWs electrodes are intrinsically stretchable and suitable for electrochemical biosensing.
• The low-cost fabrication and excellent performance under strain position v-AuNWs as a promising platform for next-generation conformally integrated in vivo biodiagnostics.