Hierarchical Co(OH)F@NiCoAl-LDH Core–Shell Architectures Derived from Co(OH)F Nanowire@ZIF-67 Intermediates for High‑Performance Supercapacitors

Developing high-performance positive electrode materials is critical for advancing supercapacitor technology. Layered double hydroxides (LDHs) typically suffer from poor electronic conductivity and limited cycling stability. Herein, we rationally constructed hierarchical core–shell Co(OH)F@NiCoAl-LDH electrodes on nickel foam via an in situ ZIF-67 transformation strategy. The one-dimensional Co(OH)F core may facilitate electron transport between the active LDH shell and the current collector, while the open two-dimensional LDH nanosheet shell improves electrolyte accessibility. The optimized Co(OH)F@NCA-LDH-4 electrode delivers a high specific capacitance of 2746 F g–1 at 1 A g–1 and retains 67.11% of its initial capacitance after 10,000 cycles, significantly outperforming the Al-free control electrode (41.10%). When assembled with an activated carbon negative electrode, the asymmetric supercapacitor achieves a specific capacitance of approximately 139 F g–1 at 1 A g–1, retains 66.67% after 5000 cycles at 10 A g–1, and reaches an energy density of 53.75 Wh kg–1 at 900 W kg–1. This work provides a feasible strategy for constructing advanced LDH-based electrodes with enhanced conductivity and stability.