Interface-engineered binder-free NiFe LDH–MXene nanocomposite for improved charge storage in solid-state asymmetric supercapacitor devices
摘要
Nickel–iron-layered double hydroxides (NiFe-LDH) are known for their strong electrochemical activity and low cost, yet their practical use in energy-storage devices is restricted by limited electrical conductivity and sluggish ion transport. To address these limitations, conductive additives are commonly incorporated into hydroxide frameworks to enhance charge mobility and overall electrochemical response. In this study, a binder-free NiFe-LDH/Ti3C2Tₓ MXene nanocomposite was fabricated through a hydrothermal synthesis route and then applied as a supercapacitor electrode. Material characterization results confirmed the successful formation of NiFe-LDH with uniformly dispersed MXene sheets, yielding a nanoflower-like hierarchical structure. Such architecture increased the accessible surface area and generated a highly porous network, both of which promoted efficient electrochemical reactions. Electrochemical evaluation of the prepared electrode revealed a specific capacitance of 1512 F g−1 at 0.75 A g−1, along with strong rate performance. Furthermore, the assembled asymmetric supercapacitor delivered an energy density of 47.25 Wh kg−1 and a power density of 700 W kg−1, while retaining 65% of its capacitance after 10,000 charge–discharge cycles. The performance was improved compared to previous work on NiFe LDH due to strong interfacial coupling between LDH nanosheets and functionalized MXene surfaces.
Graphical abstract