Why 2D Sheets Block Ions and Tiny Scrolls Don't

For nearly fifteen years, MXenes were a two-dimensional material in search of a third dimension. Drexel University discovered the class of conductive nanomaterials in 2011, found them extraordinarily useful in their flat sheet form, and spent the next decade applying them to energy storage, water desalination, and electromagnetic shielding. Then someone asked what would happen if you rolled them up.

The answer, published in Advanced Materials, is the MXene nanoscroll: a one-dimensional cousin of the 2D flake, made by a water-based chemical process that peels and curls flat MXene sheets into tight tubular structures roughly ten thousand times thinner than a water pipe. The result is more conductive than the flat version it came from and opens up ion transport paths that stacked 2D sheets actively block.

The process is called a Janus reaction. By precisely controlling the chemical environment around a multilayer MXene flake, the researchers alter surface chemistry asymmetrically, creating lattice strain within the layers. The strain releases by peeling the layers apart and curling them into scrolls. According to the Drexel team, the team tested it across six MXene compositions: two types of titanium carbide, niobium carbide, vanadium carbide, tantalum carbide, and titanium carbonitride. Each produced nanoscrolls with controllable chemical composition and physical structure, at batches of roughly ten grams.

That matters for manufacturing. Previous attempts to make MXene nanoscrolls produced inconsistent results, per the researchers. The new method is described as scalable, which is a different claim than saying it is manufactured at scale. Lab batches of ten grams are not a production line. But the process itself is not exotic chemistry. It uses water. That is a meaningful constraint lifted.

The structural advantage over 2D sheets is geometric. When MXene flakes stack flat, ions traveling through a battery or desalination membrane have to navigate the space between layers, a path the researchers call nano-confinement. The flat sheets pack densely, and the interlayer galleries are narrow. The scroll geometry eliminates this. The tubular structure is open. Teng Zhang, a postdoctoral researcher at Drexel and co-author of the paper, described it as creating highways for rapid ion transport, allowing ions to move freely.

The conductivity claim is directional but not quantified in accessible sources. Every coverage source describes the scrolls as more conductive than their 2D counterparts. None provides a conductivity value in siemens per centimeter. The paper almost certainly contains that number. The paywall does not.

The biosensor application follows the same logic. Stacked 2D MXene sheets hide their active surface sites between layers, making it difficult for large molecules to reach them. The hollow open structure of a scroll exposes the MXene surface directly to whatever analyte is being measured. Gogotsi called it ensuring a strong, stable signal.

The more striking finding is superconductivity. Niobium carbide MXene in its flat pressed-pellet form does not superconduct. When rolled into nanoscrolls and processed into free-standing macroscopic films, it does. Gogotsi described this as the first time superconductivity in this MXene class has been realized in a solution-processed film with mechanical flexibility. The mechanism is a hypothesis: the scrolling process introduces lattice strain and curvature absent in flat sheets, which the researchers propose stabilizes the superconducting state. The paper acknowledges the exact physics is still being explored. That is an honest caveat from authors promoting their own result.

The wearable electronics application is speculative but plausible. The scrolls provide mechanical reinforcement in a polymer matrix because they are rigid relative to the soft polymer, while simultaneously maintaining a conductive network. The researchers note an electric field can orient the scrolls during processing, meaning they could be aligned along the axis of fibers in a functional textile. This is described as future work, not demonstrated hardware.

What the accessible sources do not contain is independent verification of any performance claim, quantitative ion transport data, or commentary from researchers not affiliated with Drexel. Every secondary source the paper produced is a Drexel press release or a wire summary of it. The paper was published January 22, 2026 in Advanced Materials. The coverage arrived in late January and again in late March. Nothing independent has surfaced in the interval.

The story is real science with a real published result. The synthesis method works, the scroll geometry provides a genuine ion transport advantage over 2D sheets, and the superconductivity finding in niobium carbide is a legitimate first. Whether that specific finding generalizes to practical superconducting devices is an open question the paper does not answer. The ion highway framing is marketing language from the authors. The underlying physics is solid.