High-yield and high-throughput delamination of multilayer MXene via high-pressure homogenization

Two-dimensional (2D) MXenes are a large family of materials with unique properties and numerous potential applications. They are typically produced by selective chemical etching of MAX phase precursors, which is a topdown approach allowing for scalable manufacturing. Multilayer MXenes are then further processed by chemical intercalation and delamination to produce a stable dispersion of 2D flakes in water. The current process of delamination requires multiple time-, energy-, and waste-intensive steps and still fails to delaminate some MXenes. Herein, we demonstrate a method of high-energy delamination called high-pressure homogenization (HPH) that combines high shear, cavitation forces, and impact forces to delaminate MXene without any postprocess refinement steps or chemical intercalants. HPH-delaminated MXene can be made at scale with high throughput and yield with virtually no waste. We demonstrate the viability of this process by fabricating freestanding films with the material for use as electrodes for energy storage and as an effective antimicrobial coating where any residual lithium is undesirable. HPH-MXene electrodes demonstrated comparable capacitance to that of lithium-delaminated films with better rate capability. HPH-MXene films proved effective as antimicrobial coatings with over a two-log reduction in pathogenic microbes without the concern of chemical leaching by the coating. We anticipate that this method will decrease the cost of MXene manufacturing and be applicable to a variety MXenes, including those that cannot be currently delaminated via intercalation.