Controlled preparation of cobalt carbonate hydroxide@nickel aluminum layered double hydroxide core-shell heterostructure for advanced supercapacitors

Herein, we report the rational fabrication of unique core-shell nanoclusters composed of cobalt carbonate hy-droxide (Co-CH) @ nickel aluminum layered double hydroxide (NiAl-LDH) on a carbon cloth (CC) substrate using a two-step hydrothermal strategy. The one-dimensional (1D) Co-CH nanowires core-shell functions as a framework for the growth of two-dimensional (2D) NiAl-LDH nanosheets, leading to the formation of a hier-archically porous core-shell heterostructure. The presence of abundant heterointerfaces enhances electrical conductivity, reduces charge transfer resistance, and facilitates ion/electron transfer. Taking full advantage of its unique nanostructure and synergistic effect of two components, the as-prepared Co-CH@NiAl-LDH hybrid ma-terial illustrates a specific capacity of 1029.4 C/g (2058.9 mC cm-2) at 1 A g-1 and good rate capability with a capacity retention of 68.5% at 20 A g-1. Additionally, the assembled Co-CH@NiAl-LDH//pine pollen-derived porous carbon (PPC) hybrid supercapacitor (HSC) delivers impressive energy and power densities of 66.2 Wh kg- 1 (0.27 Wh cm-2) and 17529.7 Wh kg- 1 (0.11 Wh cm-2), respectively. This device also achieves a superior capacity retention of 80.3% over 20,000 cycles. These findings prove the importance of engineering hetero-interfaces in heterostructure for the promotion of energy storage performance.

Automated summary

In this study, we successfully synthesized unique core-shell nanoclusters composed of Co-CH@NiAl-LDH on a carbon cloth substrate using a two-step hydrothermal strategy. The presence of abundant heterointerfaces in the hierarchical porous core-shell structure enhances conductivity and facilitates ion/electron transfer. The as-prepared Co-CH@NiAl-LDH hybrid material exhibits high specific capacity and excellent rate capability, and the assembled hybrid supercapacitor demonstrates impressive energy and power densities, as well as superior capacity retention.