Hierarchical structure of in-situ Fe₂O₃ nanoparticles decorated on crumpled Ti₃C₂T_x nanosheets with enhanced cycle performance as anode for lithium ion battery

This paper presents a simple wet-chemical method for preparing hierarchical Fe₂O₃@Ti₃C₂T_x nanocomposites with 50–70 wt% Fe₂O₃ based on hydrothermal synthesis followed by freeze-drying. In this method, positively charged Fe₂O₃ nanoparticles homogeneously nucleate in-situ, grow, and are electrostatically anchored on the surface of negatively charged and crumpled Ti₃C₂T_x nanosheets. The synergy between the Fe₂O₃ and Ti₃C₂T_x inhibits the agglomeration and grain growth of the Fe₂O₃ nanoparticles, prevents the restacking and oxidation of the Ti₃C₂T_x nanosheets, and provides abundant voids, thus significantly improving the charge transport kinetics of the composite and absorbing the expansion of the Fe₂O₃ nanoparticles. In this study, a 60 wt% Fe₂O₃@Ti₃C₂T_x composite showed excellent electrochemical performance as an anode for a lithium ion battery, with a capacity of 701.86 mAh g^-1 after 200 cycles at 0.2 A g^-1 and a capacity of 609.9 mAh g^-1 after 600 cycles at 0.5 A g^-1. The proposed strategy is scalable, universal applicable for constructing MXene-based hybrids, and can be potentially viable in fields such as energy storage, electromagnetic interference shielding, microwave absorbance, and catalysis.