Understanding the Capacitive and Diffusion-Controlled Behavior of Electrophoretically Deposited V2CTx on Carbon Yarn as a Potential Anode for Asymmetric Devices

Abstract

Recently, a novel class of emerging 2D materials identified as MXene have been revolutionizing the fabrication and development of flexible energy storage systems, i.e., batteries and supercapacitors. Herein, the focus is on the remarkable capacitive performance of V₂CT_x MXene-based flexible electrodes so far poorly explored. However, research was focused on Ti₃C₂T_x and its applications in the energy field, although more than 100 other members of this group have already been reported. Some of these MXenes are emerging as potential candidates for energy applications with promising results such as Ti₂C and Mo₂C in aqueous electrolytes, but many others remain to be explored. The paper detailed a comprehensive study of the electrophoretic deposition of V₂CT_x on carbon yarn wires and the evaluation of their electrochemical behavior (capacitive and diffusive) in three electrolytes at different pH values: acidic, basic, and neutral pH to investigate the correct potential window for this material in energy applications. The devices exhibited specific capacitances of 248, 177, and 89 F g^–1 for EPD10, EPD20, and EPD30, respectively. The synthesized and deposited MXene nanoparticles were analyzed by XRD, Raman, and SEM for phase identification, chemical structure identification, and morphological analysis, respectively. The synthesized material showed good electrochemical performance in terms of cyclic stability after 3000 cycles with >90% capacitance retention.