Abstract
We report the effect of the Ti3C2Tx MXene flake thickness on its inherent electrochemistry and heterogeneous charge transfer characteristics. It is shown that Ti3C2Tx undergoes irreversible oxidation in a positive potential window, which strongly depends on the flake thickness and pH of the electrolyte. Few-layered Ti3C2Tx exhibits faster electron transfer kinetics (k(0) = 0.09533 cm s(-1)) with a [Fe(CN)(6)](4-/3-) redox mediator compared to multi-layered Ti3C2Tx (k(0) = 0.00503 cm s(-1)). In addition, the few-layered free standing Ti3C2Tx film electrode remains intact after enduring irreversible oxidation.