Aligned Ti3C2Tx Electrodes Induced by Magnetic Field for High-Performance Lithium-Ion Storage

The promising two-dimensional transition-metal carbides/nitrides (named MXenes) present extremely competitive potential applications as anode of Li-ion battery owing to their advantages such as chemical diversity, superior conductivity, and high specific surface area, but the inevitable restack and collapse of interlayers hinder Li+ transport and thus severely restrict the practical applications. Herein, we designed aligned Ti3C2Tx electrodes via graphite-assisted magnetic alignment technique. The introduction of graphite not only supports Ti3C2Tx flakes to achieve the aligned structure, which is beneficial to ion diffusion, but also acts as a highly conductive medium to facilitate electron transfer. Moreover, graphite endows the lithium storage capacity, thus improving synergistically the electrochemical properties of Ti3C2Tx electrodes. Hence, combining the aligned structure of the electrode with synergistic effects, the aligned Ti3C2Tx electrode delivers 196.5 mAh g(-1) at 50 mA g(-1) and exhibits superior rate performance and long cycle stability (the specific capacity is 3.6 times more than that of the electrode without an alignment structure at 2 A g(-1) and retains 90% after 5000 cycles). The aligned Ti3C2Tx electrode is promising to achieve the practical applications. Furthermore, the magnetic alignment technique is expected to be extended to engineer other two-dimensional materials as a universal strategy for the requirement of excellent properties.