Synergistically coupling of 3D FeNi-LDH arrays with Ti3C2Tx-MXene nanosheets toward superior symmetric supercapacitor

Layered double hydroxides (LDHs) are promising energy materials for their considerable theoretical capacities and adjustable compositions, however, also subjected to the intrinsic poor conductivity and agglomeration property, hence, the precise hybridization with high conductivity and active surface matrix is an effective strategy to solve these intractable problems. Herein, we exploit hierarchical nanohybrids via ionic hetero-assembly of 3D FeNi-LDH arrays on 2D Ti3C2Tx-based MXene nanosheets through mutual coupling synergy. The strong interfacial interaction and good electronic coupling between the FeNi-LDH arrays and Ti3C2Tx MXene nanosheets not only improve the structural stability, electrical conductivity, and electrolyte-accessibility but also greatly boost the redox reaction kinetics. The obtained Fe1Ni3-LDH/Ti3C2Tx-MXene energy materials reveal prominent conductivity, superior capacitance behavior, and the constructed symmetric supercapacitor demonstrates outstanding energy densities of 94.1 Wh Kg-1 and power density of 7431.8 W Kg-1. This study offers a facile and efficient strategy for developing 2D MXene-based energy storage devices with a stable interface and favorable electrochemical performance. [Display omitted] •A new etching strategy using Ni2F with N2 intercalation and ultrasonic exfoliation to achieve a few-layer Ti3C2Tx-MXene.•FeNi-LDH nanoflowers are anchored onto the Ti3C2Tx-MXene sheets via electrostatic attraction connection.•The Ti3C2Tx-MXene not only constructs a successive conductive network, but also provide platform for the growth of FeNi-LDH.•The optimized electrode reveals prominent specific capacitance (1015 F g-1 ) and cycling stability (88% after 10000 cycles).•The symmetric supercapacitor demonstrates outstanding energy densities of 94.1 Wh Kg–1 and power density of 7431.8 W Kg–1.