Heterostructure MnO/MnSe nanoparticles encapsulated in a nitrogen-doped carbon shell for high-performance lithium/sodium-ion batteries

Heterostructure MnO/MnSe nanoparticles, encapsulated in a nitrogen-doped carbon shell (MnO/MnSe@NC), were synthesized as anode materials using a hydrothermal approach followed situ calcination and selenization process. The NC shell, possessing high electronic conductivity, can function as a substrate to prevent nanoparticle agglomeration and mitigate volume variations. The porous nanostructures can shorten the ion diffusion path and increase active sites, thereby accelerating ion migration and ultimately enhancing battery capacity. Moreover, the MnO/MnSe heterostructure can facilitate Li+/Na+ diffusion, leading to improved rate performance. Benefiting from the structural advantage of MnO/MnSe heterostructure nanoparticles encapsulated within a nitrogen doped carbon shell, this electrode demonstrates exceptional electrochemical performance as an anode for LIBs, including a high discharge capacity (1740 mAh g−1 at 0.1 A g−1), remarking rate capability (849.9 mAh g−1 at 15.0 A g−1), and superior cycling stability (802 mAh g−1 over 1500 cycles at 5.0 A g−1). Meanwhile, the MnO/MnSe@NC serves as an anode material in SIBs, demonstrating a remarkable reversible specific capacity of 902.8 mAh g−1 at 0.1 A g−1 and excellent rate capability (681.6 mAh g−1 at 15.0 A g−1). The present study presents a straightforward approach for fabricating the anode electrode of high-performance lithium/sodium ion batteries.