Investigating the Synergistic Effect of Cus@Ti3c2tx/Mxene for Supercapacitors and Water Splitting Applications

Abstract

Energy storage and water electrolysis for hydrogen production stand as critical applications in electrochemistry, emphasizing the need for appropriate electrodes. During last few years, the spotlight has turned to 2-dimensional (2D) materials, especially MXene with its 2-dimensional structure and excellent conductivity, owing to their potential in green chemistry applications. Therefore, the synthesis of CuS@Ti3C2Tx/MXene nanocomposites through solvothermal synthesis, incorporating copper sulfide (CuS) into 2-dimensional MXene sheets, significantly boosts the electrochemical performance of electrodes. This advancement is attributed to the synergistic effects between the components, which facilitate improved electron transfer rates and effectively inhibit the agglomeration of CuS nanoparticles. Consequently, this contributes to the improvement of energy storage characteristics, while also enhancing both the hydrogen evolution reaction (HER) and oxygen evolution reaction (OER). Cyclic voltammetry testing revealed an enhanced current density in CuS@Ti3C2Tx/MXene compared to individual CuS and Ti3C2Tx/MXene electrodes, indicating superior electrochemical performance of the composite material. The CuS@Ti3C2Tx/MXene demonstrated enhanced specific capacity of 2550.4 F g-1 at 1 A g-1 and retains high cyclic stability (96% capacity retention over 10,000 cycles) while individually CuS nanoparticles achieves 1758 F g-1 and capacity retention remains 68.5% after 10,000 cycles. CuS@Ti3C2TxMXene electrode shows high pseudo capacitance ratio of 90.3% at 5 mV s-1 compared to 65.3% of CuS. CuS@Ti3C2Tx/MXene composite electrode shows remarkable performance for LSV test. Specifically, it achieved a minimum overpotential of 132 mV with a Tafel slope of 54 mV dec-1 at a current density of 10 mA cm-2 for HER, and an overpotential of 225 mV with a Tafel slope of 39 mV dec-1 at 30 mA cm-2 for OER. These results suggest that 2D material-based nanoparticles hold as promising electrode for enhancing electrochemical performance related for supercapacitor and water splitting, pointing towards their potential use in future green energy applications.

Keywords: electrochemical properties, Supercapacitors, synergistic effect, Copper sulfide, CuS@Ti3C2Tx/MXene, Green energy.