Inherent electrochemistry and charge transfer properties of few-layered two-dimensional Ti3C2Tx MXene

Abstract

We report the effect of the Ti₃C₂T_x MXene flake thickness on its inherent electrochemistry and heterogeneous charge transfer characteristics. It is shown that Ti₃C₂T_x undergoes irreversible oxidation in a positive potential window, which strongly depends on the flake thickness and pH of the electrolyte. Few-layered Ti₃C₂T_x exhibits faster electron transfer kinetics (k⁰ = 0.09533 cm s⁻¹) with a [Fe(CN)₆]^4−/3− redox mediator compared to multi-layered Ti₃C₂T_x (k⁰ = 0.00503 cm s⁻¹). In addition, the few-layered free standing Ti₃C₂T_x film electrode remains intact after enduring irreversible oxidation.