Carbon Welding by Ultrafast Joule Heating.

Area of Science:

• Materials Science
• Nanotechnology
• Electrochemistry

Background:

• Carbon nanomaterials possess excellent electrical and mechanical properties.
• Assembly into bulk structures often compromises these properties due to poor inter-nanostructure contacts.
• Scaling limitations hinder the application of carbon nanostructures.

Purpose of the Study:

• To develop a novel technique for creating a 3D interconnected carbon matrix.
• To overcome limitations in scaling carbon nanomaterials for practical applications.
• To enhance the electrical conductivity and mechanical integrity of carbon structures.

Main Methods:

• Utilized high-temperature Joule heating ( > 2500 K) on carbon nanofiber (CNF) films.
• Applied a rapid heating rate (200 K/min) to induce graphitization.
• Formed covalent graphitic carbon bonds between adjacent CNFs to create a continuous network.

Main Results:

• Achieved a four-order-of-magnitude increase in bulk electrical conductivity to 380 S/cm.
• Obtained a low sheet resistance of 1.75 Ω/sq.
• Successfully formed a 3D continuous carbon network with enhanced properties.

Conclusions:

• High-temperature Joule heating is an effective strategy for fast graphitization and creating covalently bonded graphitic carbon networks.
• The 3D interconnected carbon matrix exhibits high electrical conductivity, good mechanical structure, and anticorrosion properties.
• The developed carbon membrane shows significant potential for applications in energy storage and electrocatalysis.