Speaker
Description
MXenes are a class of two-dimensional materials attracting considerable attention owing to their distinctive physical and chemical properties, which are governed by their surface terminations (Tx). Titanium carbide (Ti3C2Tx) is the most extensively studied MXene, having demonstrated exceptional electrical conductivity, electromagnetic shielding, photonic, and tribological properties.[1] Although upscaling strategies for Ti3C2Tx are actively being explored, a fundamental limitation remains in the synthesis approach. MXenes are conventionally synthesized by employing strong acids (e.g., hydrofluoric acid) to selectively cleave the bonds of the A-group element from their precursor phases (i.e., MAX phases). The handling and use of HF, even in less aggressive synthesis routes such as the MILD method, poses considerable risks to users and the environment, particularly with respect to waste management.
Electrochemical synthesis has emerged as a promising alternative for the sustainable production of MXenes; however, its primary limitation has been the achievable yield, which can be severely compromised by the formation of MXene clusters and byproducts on the MAX electrode surface. As a consequence, toxic or hazardous chemicals (e.g., TMAOH) have frequently been employed as synthesis auxiliaries.
Here, we propose a paradigm shift in addressing this challenge. Rather than focusing on electrolyte composition, we demonstrate the critical role of the applied potential waveform, a parameter held constant in previous studies. By employing pulsed voltammetry to apply reverse cathodic pulses, we promote hydrogen evolution at the MAX electrode interface, thereby inducing the formation of surface nanobubbles. These interfacial objects locally modify intermolecular forces (e.g., adhesion) and facilitate the detachment of MXene flakes and byproducts from the MAX electrode into the electrolyte.[2]
The controlled formation of surface nanobubbles enabled operando electrode reactivation, yielding electrochemically synthesized MXene (EC-MXene) with a reduced proportion of F-based terminations and a maximized density of O-based terminations. The exceptional tribological performance of EC-MXene was further validated through an integrated approach combining tribometer measurements, surface analytics, and DFT simulations. These results establish EC-MXene as a benchmark material for sustainable solid lubrication.[3]
In this talk, it will be presented the novel strategy of inducing surface nanobubble formation to regenerate electrochemically active sites on the MAX electrode. The approach opens new avenues for in situ etching synthesis. The implications of this work extend beyond this specific application, with potential relevance to nanobubble–nanoparticle interaction studies, nanocatalysis, and surface termination engineering in two-dimensional materials. Furthermore, the demonstrated application of EC-MXene as a solid lubricant initiates a broader research direction aimed at addressing global challenges in energy consumption efficiency through the development of sustainable lubricants.
Keywords: MXene; electrochemical synthesis; surface nanobubbles; pulsed voltammetry.
Acknowledgements
P.Bilotto acknowledges Gesellschaft für ForschungsfürderungNiederösterreich m.b.H.” for support through its FTI PhD Funding Programme(FTI22-D-018).
Reference
1. B. Anasori, M.R. Lukatskaya, Y. Gogotsi, Nat.Rev.Mater., 2017, 2, 16098
2. M. Ostermann, M. Piljevic, E. Akbari, P. Patil, V. Zahorodna, I. Baginskiy, O. Gogotsi, C. Gachot, M. Rodriguez Ripoll, M. Valtiner, P. Bilotto, Small, 2025, 2500807
3. M. Piljevic, M. Ostermann, E. Marquis, S. Schwarz, M. Stöger-Pollach, O. Gogotsi, M. Valtiner, M. Rodriguez Ripoll, C. Gachot, P. Bilotto. Carbon, 2026, 248, 121136