Growing Magnetic NiCo-LDH Nanosheets on the Ni@CoSe 2 Surface to Enhance Energy Storage Capacity in Asymmetric Supercapacitors

作者：Yi Gao, Yi Jiang, Bin Cai, Hao Gu, Ruixiang Xu, Yuxin Sun, Jingwei Zhou, Fei Yu · 发表于：ACS Applied Energy Materials · 年份：2025 · DOI：10.1021/acsaem.4c02788 · 被引用次数：20 · 研究领域：Supercapacitor Materials and Fabrication、Advancements in Battery Materials、Advanced battery technologies research

Nickel–cobalt layered double hydroxide (NiCo-LDH) shows great potential as an electrode material for various applications; however, single NiCo-LDH layered electrode materials are poorly stabilized and prone to agglomeration, which hampers ion transport. In this study, three-dimensional composite electrode materials with high specific surface area and abundant redox active sites were prepared by loading spherical CoSe 2 on the surface of nickel foam and realizing the in situ growth of NiCo-LDH nanosheets derived from ZIF-67 on the Ni@CoSe 2 skeleton. The results show that the CoSe 2 @NiCo-LDH electrode achieves an area-specific capacitance of 6.06 F cm –2 at a current density of 6 mA cm –2 . Compared with CoSe 2 and NiCo-LDH, CoSe 2 @NiCo-LDH electrodes have a 0.265 eV narrow bandgap. It is demonstrated that the composite heterojunction of CoSe 2 and NiCo-LDH enhances the electrical conductivity, and the built-in electric field triggered by efficient electron migration promotes the conductivity and electrochemical activity of the electrode materials. The charge density distribution and density of states further confirm that the interaction between CoSe 2 and NiCo-LDH heterojunctions mainly relies on the hybridization of d orbitals of Co atoms, Ni atoms, and p orbitals of Se atoms, which facilitates charge transport and ion diffusion. Molecular dynamics simulations show that the composite exhibits excellent ion adsorption capacity in KOH electrolyte. An asymmetric supercapacit...