Nearly 15 years after discovering MXenes, a versatile class of two-dimensional conductive nanomaterials, researchers at Drexel University have developed a method to create one-dimensional versions known as MXene nanoscrolls. These ultra-thin structures are about 100 times thinner than a human hair and are even more conductive than flat structures, potentially enabling significant improvements in technologies such as energy storage devices, biosensors, and wearable electronics.
Research published in journals advanced materialspresent a scalable method to fabricate these nanoscrolls from MXene precursors with precise control over their shape and chemical composition.
“Two-dimensional morphology is very important in many applications, but there are some applications where one-dimensional morphology is better,” said corresponding author Dr. Yuri Gogotsy, Bach Professor at the prestigious Drexel Institute of Technology. “It’s like comparing steel plates to metal pipes and rebar. You need steel plates to make the body of a car, but you need long tubes and rods to pump water or reinforce concrete.”
From flat sheets to tubular nanostructures
The researchers created the nanoscrolls by rolling flat MXene flakes into tiny tubular structures about 10,000 times thinner than a water pipe. These tubular materials can strengthen polymers and metals or guide the movement of ions in batteries or desalination systems with much less resistance.
“In a standard 2D MXene, the flakes lie flat on top of each other, creating limited space and difficult paths for ions and molecules to migrate and move between layers,” said Teng Zhang, Ph.D., a postdoctoral fellow in the School of Engineering and co-author of the study. “Converting 2D nanosheets into 1D scrolls prevents this nanoconfinement effect. The open tubular shape effectively forms a ‘highway’ for rapid transport, allowing ions to move freely.”
Although similar structures made from graphene, such as carbon nanotubes, are already well known, producing MXene nanoscrolls of consistent high quality has been difficult. Although MXene has advantages over graphene, including richer chemistry, easier processing, and higher electrical conductivity, early attempts to form scrolls often yielded uneven results.
A scalable method to fabricate MXene nanoscrolls
To make nanoscrolls, researchers start with multilayered MXene flakes. Water is used to change the surface chemistry of materials by carefully adjusting the chemical environment. This causes a structural imbalance called a Janus reaction, which creates internal strains within the layer. When this strain is released, the layers peel off and curl into tight scrolls.
The research team successfully applied this method to six types of MXene, including two types of titanium carbide, niobium carbide, vanadium carbide, tantalum carbide, and titanium carbonitride. They were able to consistently produce 10-g nanoscrolls with controlled chemical and physical properties.
Improved conductivity and sensing ability
The scroll-like structure not only improves electrical conductivity and mechanical strength, but also changes the way the material and molecules interact. This makes them particularly promising for sensing applications and advanced composite materials.
“In standard stacked 2D structures, the active sites for molecular adsorption are often hidden between the layers, making it difficult for molecules, especially large biomolecules, to reach them,” Gogozzi said. “The open hollow structure of the scroll allows the analyte to easily access the MXene surface, solving this problem. Combined with the material’s high electrical conductivity and mechanical stiffness, it ensures a strong and stable signal. Therefore, we We envision the use of scrolls in biosensing. The same accessible surface of conductive scrolls could be useful for gas sensors, electrochemical capacitors, and other devices that require ion or molecular access to the surface.”
Applications in wearable electronics and smart textiles
Researchers also see strong potential for MXene nanoscrolls in wearable electronics, also known as ionotronic devices. In these systems, scrolls can strengthen the material and improve its conductivity. The rigid structure is anchored within a soft polymer, increasing strength while maintaining a reliable conductive network.
This combination could result in a stretchable material that remains functional despite repeated bending and movement.
The research team also discovered that the orientation of the nanoscrolls in solution could be controlled using an electric field. This means that it can be aligned with the fibers of textiles to create more durable and conductive coatings for smart fabrics.
“Imagine manipulating millions of tubules that are 100 times thinner than a human hair to create a wire or stand vertically to create a brush,” Zhang said. “This is true nanotechnology because we can manipulate materials at the nanoscale. It’s also an important development for functional fibers because scrolls can be incorporated as reinforcement in synthetic fibers.”
Superconductivity and future quantum applications
The researchers now plan to further investigate how these nanoscrolls behave at the quantum level, particularly the possibility of superconductivity.
“Until now, superconductivity in this class of MXenes has been limited to pressed pellets of particles or powders, and not achievable in solution-processed films with mechanical flexibility,” Gogozzi said. “Using scrolls of niobium carbide, we observed for the first time sufficient changes in the material to enable superconductivity in free-standing, macroscopic thin films. The scrolling process introduces certain lattice strains and curvatures that are not present in flat sheets. Although the exact physical mechanism is still under investigation, we hypothesize that this strain, combined with the continuous 1D structure, stabilizes the superconducting state.”
As interest in quantum materials grows, nanomaterials like MXene are gaining attention for their ability to improve computing power and data storage. This work represents an important step forward by turning MXene superconductors into more practical and usable properties.
“Using the method described in this paper, superconducting MXenes can be processed into flexible films, coatings, or wires at room temperature that can be used as candidates for superconducting interconnects and quantum sensors,” Zhang said. “We expect many other interesting phenomena caused by scrolling and intend to study them.”
