In a study published in Small, they demonstrated that wires and fabrics made from CNTFs can deliver substantially more heating power per unit mass than conventional metal-alloy heaters when placed directly in flowing gases, paving a potential new pathway for electrifying industrial heating, a critical but technically challenging step toward reducing carbon emissions.
US researchers have developed a type of electric heating element using carbon nanotube fibres (CNTFs).
They demonstrated that CNTF wires and fabrics can deliver substantially more heating power per unit mass than conventional metal-alloy heaters when placed directly in flowing gases.
A distinctive feature of the work is its reliance on textile-inspired manufacturing techniques.
“Electrifying industrial heat is one of the most important, and most difficult, pieces of decarbonisation,” said first author Monisha Vijay Kumar, a graduate student in applied physics, in a release from the university.
Industrial facilities routinely heat gases for processes ranging from chemical production and drying to thermal treatment and manufacturing. Today, that heat is typically generated by burning fuels.
While electric heating may sound simple—passing current through a resistive element—heating moving gases imposes severe demands on materials and design. Heaters must transfer energy rapidly and evenly into the gas stream while avoiding destructive hot spots, mechanical deformation and failure under extreme temperatures.
Placing heating elements directly in the gas flow (immersion heating) improves efficiency, but significantly increases stress on the material.
One of the most stubborn constraints is size. Thinner heating elements exchange heat with gases more effectively, but conventional metal alloys are difficult to fabricate and handle at very small diameters.
CNTFs offer a striking alternative; they combine electrical resistivity suitable for Joule heating with exceptional strength-to-weight ratios and unusually high thermal conductivity compared with traditional heater materials, the university release said.
Carbon nanotube fibres behave very differently from metal wires, and are lightweight, flexible and remarkably strong, which allows consideration of heater geometries and fabrication techniques that would be impractical with conventional materials.
Rather than adapting CNTFs to existing heater designs, the team built devices made entirely from the fibres, including single filaments, parallel arrays and textile-like fabrics. Their key performance metric was specific power loading—the maximum heating power per unit mass a device can sustain before failure.
Across multiple configurations and operating conditions, CNTF heaters consistently achieved higher specific power loadings than comparable metal-alloy elements, the team reported in the journal.
The advantage was particularly pronounced in non-oxidising environments, where carbon-based materials can withstand far higher temperatures without degradation. From a heat-transfer perspective, the fibres’ thermal properties proved especially important.
A distinctive feature of the work is its reliance on textile-inspired manufacturing techniques. CNTF yarns can be woven, knitted and assembled into lightweight, high-surface area structures—geometries that are particularly well suited for immersion heating.
Compared with rigid metal meshes, CNTF fabrics exhibited more uniform heating behaviour and reduced hot spot formation, benefits again linked to the fibres’ ability to spread heat efficiently.
This research was supported by the National Science Foundation, the US Department of Energy, Shell, the Welch Foundation, the Carbon Hub, a NASA Space Technology Graduate Research Opportunity award and a National GEM Consortium Fellowship.
Fibre2Fashion News Desk (DS)
