Synthesis of CoO-anchored nickel-cobalt layered hydroxide nanowire arrays via low-cobalt hydrothermal method for high-performance supercapacitors

To address the challenges of reduced ion penetration channels, low active material utilization, and hindered charge transport in carbon fiber-supported nickel-cobalt layered double hydroxide (NiCo-LDH) with high mass loading (>5 mg cm -2 ), this study optimized the morphological structure of NiCo-LDH by regulating nickel/cobalt feeding ratios, achieving enhanced electrochemical performance with reduced cobalt content. The introduction of cobalt oxide (CoO) nanobridges not only provided effective anchoring sites for NiCo-LDH growth but also improved electron transport pathways. The as-prepared NiCo-10 composite exhibited a high specific capacitance of 2354 F g⁻¹ at 1 A g⁻¹. When assembled into an asymmetric supercapacitor, the device delivered an energy density of 55.8 Wh kg⁻¹ at 1070.7 W kg⁻¹ power density, with 91.39% capacitance retention after 10,000 charge-discharge cycles. These results demonstrate the superior electrochemical performance, rate capability, and cycling stability of the NiCo-10 composite, highlighting its potential for high-capacity supercapacitor applications. • Cobalt oxide anchors nickel cobalt hydroxide, constructing a high-speed electron transport channel. • Nickel cobalt hydroxide grown vertically and interlaced promotes the rapid diffusion of electrolyte ions. • The optimization of electrochemical performance under low cobalt consumption is achieved by coordinating the effective mass of nickel and cobalt.