Dimensional Effects of MoS₂ Nanoplates Embedded in Carbon Nanofibers for Bifunctional Li and Na Insertion and Conversion Reactions

Controlling structural and morphological features of molybdenum disulfide (MoS₂) nanoplates determines anode reaction performance for Li-ion and Na-ion batteries. In this work, we investigate dimensional effects of MoS₂ nanoplates randomly embedded in twisted mesoporous carbon nanofibers (MoS₂@MCNFs) on Li and Na storage properties. Considering dimensions of the MoS₂ nanoplates (e.g., interlayer, lateral distance, and slabs of stacking in number), we controlled thermolysis temperature to synthesize the MoS₂ nanoplates with different geometry and optimize them in the hybrid anode for delivering high performance. The MoS₂@MCNFs electrode exhibits reversible Li and Na capacities greater than 1000 cycles even at high current density of 1.0 A g^-1 (1221.94 mAh g^-1 with capacity retention of 95.6% for Li-ion batteries and 447.29 mAh g^-1 with capacity retention of 87.11% for Na-ion batteries). We elucidated the insertion, conversion, and interfacial reaction characteristics of the thermosensitive MoS₂ nanoplates in the MCNFs, especially associated with a reversible capacity. Our study will hint at rational design of the nanostructured MoS₂ electrodes and focus on significance of their dimensional effects on anode performance.