Heterostructured Nanocomposites of NiCo–S@Ni(OH)₂ on Ni Foam for High-Performance Supercapacitors

The development of composite materials is a key area of research for enhancing the electrochemical performance of electrode materials. In this study, NiCo–S nanostructured hybrid electrode materials were prepared on nickel foam (NF) by using binary metal–organic frameworks (MOFs) as the sacrificial template through a two-step hydrothermal method. Ni–MOF was then deposited on the surface of NiCo–S/NF through the hydrothermal method and subsequently converted into Ni(OH) 2 through a subsequent alkalization treatment. The duration of the Ni–MOF hydrothermal process was varied as a parameter. NiCo–S@Ni–MOF/NF was prepared through hydrothermal reaction for 6[Formula: see text]h, 9[Formula: see text]h and 12[Formula: see text]h, followed by heating in a 6[Formula: see text]M KOH solution at 75[Formula: see text]C for 6[Formula: see text]h in a water bath. The electrode materials with the best morphology and electrochemical properties were obtained when the hydrothermal reaction time was 6[Formula: see text]h. The optimized electrode had a specific capacity of 2533.2[Formula: see text]F[Formula: see text]g[Formula: see text] at 1[Formula: see text]A[Formula: see text]g[Formula: see text] and a capacity retention rate of 60.8% at 10[Formula: see text]A[Formula: see text]g[Formula: see text], which indicated good rate performance. Additionally, the electrode material demonstrated excellent cycling stability, with a capacity retention rate of 95.3% after 5000 cycles at 50[Formula: see text]mV[Formula: see text]s[Formula: see text]. The energy density of the hybrid supercapacitor device assembled from this electrode material was 33.5[Formula: see text]Wh[Formula: see text]kg[Formula: see text] when the power density was 849.89[Formula: see text]W[Formula: see text]kg[Formula: see text] at a current density of 1[Formula: see text]A[Formula: see text]g[Formula: see text].