Heterogeneous Fe Doped NiCo-layered Double Hydroxides Grown on Nickel Foam Induce Spin Exchange Interactions for Magnetization and High-Performance Supercapacitor Applications

Supercapacitors have attained many attentions since their unique features of high power density and excellent cycle life. However, the great challenge for practical applications is that the energy density is much lower than fuel batteries. Herein, we develop a simple strategy to rationally design nanostructured FeNiCo-Layered Double Hydroxides (LDHs) self-assembled on 3D nickel foam (NF) by using a hydrothermal technique and their supercapacitors behaviors are studied in this works. Benefiting from the synergistic modulation of redox-active sites, Faradaic redox reaction and spin exchange interactions, FeNiCo-LDHs/NF displays ferromagnetism at room temperature and shows advanced supercapacitor property with a high specific capacity of 2284.7 F g-1 at 2 A g-1. Furthermore, an asymmetric supercapacitor (ASC) is assembled using FeNiCo-LDHs/NF as the anode and active carbon (AC) as the cathode, exhibiting excellent supercapacitor property. A considerable energy density is up to 133.7 W h kg -1 at a power density of 3.2 kW kg -1 and the capacitance is retained at 97.9% even after 5000 cycles. The results can provide an efficient fabrication for further advancing the energy density of bimetallic LDHs in energy storage applications.