Carbon nanotube fibres offer new path to electrify industrial heating and cut emissions

Researchers at Rice University have demonstrated that fibres made from carbon nanotubes can function as high-performance electric heating elements in moving gases, a development that could materially aid efforts to electrify industrial heat and cut process emissions.

The team tested arrays of carbon nanotube fibre (CNTF) wires and woven CNTF textiles, finding that for a given mass the materials delivered greater specific power than comparable metal-alloy elements when immersed in flowing gas streams. According to Rice University, the fibres combine exceptional electrical conductivity, mechanical strength and thermal transport, properties that enable compact, lightweight heater geometries with high surface area and resilience to erosion from gas flow. “When you immerse a heater directly into a gas stream, you gain heat-transfer efficiency, but you also create a much harsher operating environment,” said Rice assistant professor Daniel J. Preston, whose laboratory led the work. First author Monisha Vijay Kumar emphasised the decarbonisation opportunity, noting the difficulty of electrifying industrial heat and the appeal of an alternative material class.

The researchers report two practical advantages for industrial applications. First, woven CNTF architectures provide large, porous heating surfaces that promote even gas exposure while remaining mechanically compliant. Co-author Vanessa Sanchez highlighted textile manufacturing techniques as enabling three-dimensional heater designs that are both lightweight and electrically functional. Second, the materials produced more uniform temperature fields with fewer local hot spots than traditional coiled metal elements, reducing a common failure mode in industrial heaters.

The Rice findings build on prior demonstrations of functional CNT textiles and devices. Earlier work from the university group showed that woven CNTF fabrics could also act as flexible thermoelectric generators for energy harvesting, illustrating the material class’s versatility. Independently developed commercial applications have already moved CNT heating into garments; Eco Smart International Limited says it has completed laboratory and field validation of CNT-based heaters across a line of smart apparel, positioning the company at the leading edge of wearable thermal management.

The CNTF heater approach contrasts with other recent nanotube research that targets thermal insulation rather than heating. Researchers at Tsinghua University have reported super-aligned carbon nanotube films with record-low effective thermal conductivity at both ambient and extreme temperatures, demonstrating how nanotube architectures can be engineered to suppress heat transfer. Those results underscore that the thermal behaviour of nanotube assemblies depends strongly on macroscopic structure and intended function.

Fundamentally, the Rice results exploit Joule heating in confined, high-conductivity filaments; related physics has been explored elsewhere, for example in experiments that demonstrated remote transfer of heat from current-carrying nanotubes to nearby substrates. Such phenomena indicate a broad toolbox for tailoring heat delivery and removal at small scales, which could be valuable when integrating novel heaters into process equipment.

Electrifying heat in industry is widely viewed as among the most challenging elements of deep decarbonisation. According to a policy brief by the American Council for an Energy‑Efficient Economy, replacing industrial processes that require temperatures below 300°C with clean electricity by 2050 could lower total greenhouse gas emissions by roughly 30 percent. Rice’s CNTF heaters would target a subset of processes where direct-gas heating is currently accomplished with metal coils or combustion, including dryers, sterilisation, some thermal treatments and certain gas-driven thermal reactors.

Practical adoption will hinge on several engineering and economic questions that remain to be resolved. These include long-term durability in reactive or particulate-laden gas streams, scaling of production of consistent, high-quality CNTF at industrial volumes, integration with existing control and safety systems, and total cost of ownership compared with incumbent resistance or flame-based systems. The Rice team’s demonstration that CNTF heaters can survive the mechanical stresses of flowing gas and deliver high specific power is an important step, but industry deployment will require validation across diverse atmospheres, pressures and temperatures.

Complementary approaches are also advancing. Stanford researchers have developed electric thermochemical reactor concepts intended to provide the very high temperatures required by some metallurgical and chemical processes, demonstrating a system-level path to replace fossil-fuel heat sources. Together, device-level innovations such as CNTF heaters and reactor-level electrification pathways form a broader technical portfolio for industrial decarbonisation.

For process operators and equipment manufacturers, the Rice work suggests new design freedoms: electrically driven, permeable heater fabrics could enable compact, retrofitable heating modules that avoid the material stresses and hot-spot management problems of exposed metal coils. If subsequent testing confirms lifecycle robustness and cost competitiveness, carbon nanotube fibre heaters may become a practical option for electrifying a range of low- to moderate-temperature industrial gas‑heating applications, advancing both operational flexibility and emissions reduction goals.