Synergistic effects in mixed-dimensional CoSm2O4@SnS2@CNTs nanocomposites for enhanced asymmetric supercapacitors efficiency and hydrogen evolution reaction

초록

In this study, using a hydrothermal synthesis technique, we prepared cobalt samarium oxide (CoSm2O4) and incorporated it with SnS2 and CNTs. The composite electrode (CoSm2O4@SnS2@CNTs) demonstrated a specific capacity (Qs) of 949.71 C/g or 2110.21 F/g in a three-electrode system. In addition, we used CoSm2O4@SnS2@CNTs composite electrode with activated carbon (AC) to design an asymmetric supercapacitor device (CoSm2O4@SnS2@CNTs//AC). The asymmetric supercapacitor device exhibited a Qs of 156.19 C/g or 107.71 F/g, with an outstanding power density (Pd) of 1987 W Kg(-1) and a remarkable energy density (Ed) of 47 Wh Kg(-1). After undergoing 5000 cycles, the electrode demonstrated a capacity retention of 91.9 % along with a coulombic efficiency of 87.7 %. Besides, the CoSm2O4@SnS2@CNT nanocomposite electrode revealed a remarkable value of Tafel slope of 35 mV/dec and demonstrates a significantly lower overpotential of 39 mV in the hydrogen evolution reaction. The use of these two-dimensional composite electrodes presents novel possibilities for the creation of energy devices with exceptional performance.

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