Electrochemical study of pseudocapacitive behavior of Ti3C2Tx MXene material in aqueous electrolytes

In this paper, a multiple potential step chronoamperometry (MUSCA) technique is used to analyze the electrochemical behavior of pseudocapacitive Ti3C2Tx MXene material. MUSCA allows for reconstruction of cyclic voltammograms with considerably lower ohmic drop contribution. As such, the voltammogram current responses from the surface and bulk processes can be precisely deconvoluted at any given potentials, especially at high scan rates. An electrochemical kinetic analysis of the Ti3C2Tx electrode using the calculated voltammograms showed that the surface process dominates at higher scan rate while the bulk process takes over at the low scan rate in both acidic and alkaline electrolytes. By minimizing the ohmic drops, the MUSCA method is presented to be a useful tool to study the natural electrochemical behavior of pseudocapacitive electrodes and to help designing better energy storage systems.