A Facile Etching Route for Preparing Ti3C2 MXene with Enhanced Electrochemical Performance in Silver Nitrate Solution

Abstract

Two-dimensional Ti3C2 MXene is a promising electrode material for high-capacity supercapacitor, which is normally prepared by selective etching of the Al layer from ternary carbide Ti3AlC2 MAX phase using HF acid solution. Here a distinct etching method using a little HF acid is reported. Ti3C2 MXene decorated with Ag nanoparticles are synthesized via a chemical replacement reaction with AgNO3 solution at room temperature and then evaluated as working electrodes. Due to the synergistic effect between Ag and Ti3C2 matrix, the resulting composite of the 10 wt% AgNO3 treated sample (Ag-10) exhibits higher specific capacitance of 779.5 F g−1 at the scan rate of 5 mV s−1 in 6 M KOH electrolyte solution and shows good cycling stability with capacitance retaining 95% after 5000-cycles. This work also shows the possibility of using other metallic cations with higher redox potential to prepare high performance MXenes for supercapacitor materials.