Graphene oxide fibers by microfluidics assembly: a strategy for structural and dimensional control

Area of Science:

• Materials Science
• Nanotechnology
• Electrical Engineering

Background:

• Graphene oxide (GO) is a promising material due to its unique properties.
• Developing controlled methods for fabricating graphene-based materials is crucial for advanced applications.
• Microfluidic devices offer precise control over material synthesis and manipulation.

Purpose of the Study:

• To fabricate graphene oxide (GO) microfibers with controlled morphology using microfluidics.
• To develop reduced graphene oxide (rGO) microfibers with enhanced electrical properties.
• To demonstrate the potential of these rGO microfibers in electronic devices, specifically ionic liquid-gate field-effect transistors (FETs).

Main Methods:

• Fabrication of GO microfibers using a 3D hydrodynamic focusing technique within a microfluidic device.
• Controlled adjustments of microfiber diameters and shapes.
• Post-fabrication treatments (thermal and microwave) to convert GO to reduced graphene oxide (rGO).
• Integration of rGO microfibers into ionic liquid-gate field-effect transistor (FET) architectures.

Main Results:

• Successfully fabricated GO microfibers with homogeneous shapes and tunable diameters.
• Achieved outstanding electrical properties in the resulting rGO microfibers after thermal and microwave treatments.
• Demonstrated the functionality of rGO microfiber-based ionic liquid-gate FETs.

Conclusions:

• The 3D hydrodynamic focusing microfluidic approach is effective for producing tailored GO microfibers.
• Post-treatment significantly enhances the electrical conductivity of graphene derivative microfibers.
• These rGO microfibers are suitable for developing high-performance electronic devices like FETs.