Glycerol-mediated synthesis of copper-doped zinc sulfide with ultrathin nanoflakes for flexible energy electrode materials

Zinc sulfide (ZnS) semiconducting material possesses excellent chemical stability and efficient electrochemical properties. However, the structure of nanomaterials is highly important and crucial in achieving the desired supercapacitor (SC) performance. In this study, we prepared copper-doped zinc sulfide (Cu-ZnS) using glycerol as a co-solvent. The glycerol-mediated synthesis of Cu-ZnS resulted in nanoflake arrays with ultrathin and interconnected networks. The electrochemical performance of fabricated Cu-ZnS electrode was investigated in a three-electrode system. The Cu-ZnS electrode exhibited a high specific capacity of 297 C/g equivalent to 743 F/g at 1 A g⁻¹. Likewise, high capacity retention of 93.9 % and coulombic efficiency of 97.5 % were achieved after 5000 continuous charge-discharge cycles. The overall findings in this study revealed the superior electrochemical performance of the Cu-ZnS as an effective electrode.