Hierarchical coral-like nickel cobalt sulfides electrodes for supercapacitors

Electrode materials and their preparation are crucial components of a supercapacitor and have been the focus of related research fields. Numerous attempts have been made to enhance electrode capacity. This research focuses on preparing high mass loading hierarchical nickel and cobalt sulfides binder-free electrodes using simple techniques. Nanowire cores were first grown on a nickel foam and then used as substrates for depositing nickel and cobalt sulfides in a simple chemical bath deposition process. The resulting electrodes consist of nanowire cores covered with nanosheets of sulfides, producing a homogeneous coral-like morphology. Among the two nanowires, NiCo2(CO3)1·5(OH)3 resulted in a higher mass loading and consequently, a higher areal capacitance. However, the electrode exhibited lower rate capability and slightly lower cycle stability. Nevertheless, the obtained electrodes exhibit good electrochemical properties with a maximum areal capacitance of 2.16 F/cm2 at 10 mA/cm2. Therefore, this work demonstrates the effectiveness and flexibility of chemical bath deposition techniques in preparing hierarchical sulfide electrodes for electrochemical applications.