In-situ rooting ZnSe nanoparticles in N-doped carbon nanofibers for sodium ion batteries with ultra-long cycle life

Abstract

To encapsulate metal sulfides/selenides into carbon substrates is effective to enhance the cycling stability and rate capability of sodium-ion batteries (SIBs). In this paper, ZnSe nanoparticles rooted in N-doped carbon nanofibers (ZnSe@CNFs) were prepared by typical electrospinning technique coupled with carbonization and selenylation. As a result, ZnSe nanoparticles were wrapped by multichannel carbon fibers, which is conducive to the fast transport of sodium-ions and electrons and ensure the structural integrity. Benefiting from the special structure and the synergistic effect of two constituent, ZnSe@CNFs anode exhibits superior cycling stability of 2000 cycles at 1 A/g, with a capacity retention rate of 97.4%, equivalent to 0.0132‰ of attenuation per cycle. The carbon-encapsulation method involved in this paper has great application potential in the preparation of electrode materials.