In situ construction of N-doped Ti₃C₂T_x confined worm-like Fe₂O₃ nanoparticles by Fe-O-Ti bonding for LIBs anode with superior cycle performance

The development of Fe₂O₃ as lithium-ion batteries (LIBs) anode is greatly restricted by its poor electronic conductivity and structural stability. To solve these issues, this work presents in situ construction of three-dimensional crumpled Fe₂O₃@N-Ti₃C₂T_x composite by solvothermal-freeze-drying process, in which wormlike Fe₂O₃ nanoparticles (10-50 nm) in situ nucleated and grew on the surface of N-doped Ti₃C₂T_x nanosheets with Fe-O-Ti bonding. As a conductive matrix, N-doping endows Ti₃C₂T_x with more active sites and higher electron transfer efficiency. Meanwhile, Fe-O-Ti bonding enhances the stability of the Fe₂O₃/N-Ti₃C₂T_x interface and also acts as a pathway for electron transmission. With a large specific surface area (114.72 m² g⁻¹), the three-dimensional crumpled structure of Fe₂O₃@N-Ti₃C₂T _x facilitates the charge diffusion kinetics and enables easier exposure of the active sites. Consequently, Fe₂O₃@N-Ti₃C₂T_x composite exhibits outstanding electrochemical performance as anode for LIBs, a reversible capacity of 870.2 mAh g⁻¹ after 500 cycles at 0.5 A g⁻¹, 1129 mAh g⁻¹ after 280 cycles at 0.2 A g⁻¹ and 777.6