In Situ Constructed NiFe-LDH@Ti₃C₂T_x with a Three-Dimensional Network Structure: Enhanced Li⁺/Na⁺ Storage via an Oxygen Bridge

In this work, we employed a one-step hydrothermal method, assisted by PVP and LAA additives, to synthesize NiFe-LDH@Ti₃C₂T_x in situ with a three-dimensional network structure. The crumpled NiFe-LDH nanoflakes were anchored on the Ti₃C₂T_x surface in close face-to-face contact by heterogeneous nucleation and growth with oxygen-containing functional groups as active sites. More importantly, an oxygen bridge was simultaneously formed at the interface between NiFe-LDH and Ti₃C₂T_x, which, as an electron migration channel to form a connected conductive network, significantly enhanced the structural stability and electron migration rate. Meanwhile, the open 3D network (S_BET: 125.6 m² g^-1) facilitates the exposure of active sites and accelerates the ion migration rate, leading to excellent diffusion kinetics. As a consequence, NiFe-LDH@Ti₃C₂T_x demonstrates outstanding electrochemical stability as an anode for LIBs (987 mAh g^-1 at 0.5 A g^-1 up to 200 cycles and 912 mAh g^-1 at 1 A g^-1 up to 600 cycles) and SIBs (280 mAh g^-1 at 0.5 A g^-1 up to 200 cycles and 211 mAh g^-1 at 1 A g^-1 up to 2000 cycles).