MXenes are a group of the two-dimensional transition metal carbides, nitrides and carbonitrides, that can present features such as a good electrical conductivity, high surface area and hydrophilicity. These characteristics led MXenes to become materials of interest in the field of electrochemical sensing as they can be used to modify and improve the performance of electrochemical sensors for a variety of electroactive substances (e.g., glucose, dopamine, and cholesterol). One of the most widely used methods to obtain MXene particles is through the selective etching of their MAX phase precursor. When produced with this method, as-prepared MXene particles are usually found as agglomerates of many individual MXene layers, stacked together in parallel and bonded by van-der-Waals forces and hydrogen bonds. These are usually called accordion-like structures and their presence reduces the overall surface area and the electrical conductivity of the material. Because of this, a variety of delamination methods have been developed to reduce or avoid stacking between MXene particles. In this work, commercial Ti₃C₂T_x MXene particles were treated using three different delaminating agents (dimethyl sulfoxide, tetrabutylammonium hydroxide and lithium chloride) and the resulting products were characterized by SEM-EDS, FTIR, Raman spectroscopy and XRD techniques. Glassy carbon electrodes were modified with delaminated MXene particles by drop casting technique and sealed with a conductive polymer (chitosan). The influence of the delamination methods of Ti₃C₂T_x particles on the electrochemical response of the electrodes was studied by cyclic voltammetry using the redox system [Fe(CN)₆]³⁻ /[Fe(CN)₆]⁴⁻ in 1 M KNO₃.

Mijael Ameri

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