Scalable Synthesis of MXene Nanoscrolls

MXenes are a promising class of 2D carbides and nitrides known for their high electrical conductivity, hydrophilicity, mechanical strength, and unique optoelectronic properties, leading to numerous applications. However, their scalable synthesis in a 1D morphology, such as MXene nanotubes or scrolls, has not been demonstrated yet. This work presents a versatile and scalable method for manufacturing MXene scrolls, including Ti2CTx, Ti3C2Tx, Ti3CNTx, V2CTx, Nb2CTx, and Ta4C3Tx. We demonstrate high-yield production of up to 45 wt% of MAX phase precursor and precise control over scrolls’ alignment and morphology. Properties of scrolls differ from 2D flakes; e.g., a freestanding film made of scrolled Nb2CTx presents a transition to superconducting state below 5.2 K. Films of MXene scrolls exhibit 3 times lower density and enhanced mass transport compared to flakes, resulting in an improved performance in supercapacitor electrodes and humidity sensors. The dispersion of the scrolls in water behaves like an electrorheological fluid. Aligning scrolls in an electric field allows for circuit switching between electrically insulating and conductive states. These scrolls can be assembled into vertically aligned MXene forests, fibers, and other architectures. The availability of 1D MXene scroll offers exciting opportunities in many fields.