Inherent electrochemistry and charge transfer properties of few-layered two-dimensional Ti₃C₂T_xMXene

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 (k0 = 0.09533 cm s-1) with a [Fe(CN)6]4-/3- redox mediator compared to multi-layered Ti3C2Tx (k0 = 0.00503 cm s-1). In addition, the few-layered free standing Ti3C2Tx film electrode remains intact after enduring irreversible oxidation.

MXene Supported Cobalt Layered Double Hydroxide Nanocrystals: Facile Synthesis Route for a Synergistic Oxygen Evolution Reaction Electrocatalyst

“…In the absence of redox active species in the electrolyte, this redox peak is assigned to the oxidation of the Ti 3 C 2 T x material and especially to the oxidation of Ti atoms. [19] After the first voltammetric cycle, no further surface oxidation can be observed during the second cycle as evidenced by the disappearance of the irreversible oxidation peak centered at 0.92 V (inset graph of Figure 9a and Figure S5, Supporting Information). This shows that the surface of Ti 3 C 2 T x is then fully oxidized.…”

“…[5a] The wide range of possible substitutions in the M, X (core), and T (surface) sites of MXenes leads to a large family of 2D M n+1 X n T x materials with tunable properties opening an immense, and largely unexplored, field of potential applications. Among them, Ti 3 C 2 T x is the most studied material and several works using it as support of electrocatalyst for OER such as C 3 N 4 , [13] MOF, [14] NiCoS, [15] CoP, [16] Co/N-CNT, [17] cobalt borate, [18] FeOOH quantum dots, [19] black phosphorus quantum dots, [20] and FeNi-LDH [8b] have shown very promising performances. Nevertheless, Ti 3 C 2 T x MXene is prone to irreversible surface oxidation at ≈0.45 V versus Ag/AgCl, [21] leading to the formation of TiO 2 clusters.…”

A MXene‐Based Wearable Biosensor System for High‐Performance In Vitro Perspiration Analysis

“…The unique 2D morphology and high biocompatibility of Ti 3 C 2 T x drive great motivation to design advanced nanohybrid systems with bioreceptors like antigen–antibody, proteins, cells, and enzymes . Ti 3 C 2 T x acts as sensitive detection interface that allows facile immobilization of biomolecules for designing highly advanced detection systems and exploiting their utilization in analytical chemistry . Nonetheless, achieving the desired signal‐to‐noise ratio and stability for such sensors, especially for in situ detection, remains highly challenging.…”

MXenes for Plasmonic Photodetection

“…MXenes, a thriving family of transition metal‐based 2D materials, have garnered significant interest due to their intriguing physicochemical properties and solution processability . 2D MXene nanosheets are obtained by selectively etching away the A atoms from their parent ternary “MAX” phases constituting a large family of layered transition metal carbides, nitrides, or carbonitrides.…”