Monodisperse multicore-shell SnSb@SnOx/SbOx@C nanoparticles space-confined in 3D porous carbon networks as high-performance anode for Li-ion and Na-ion batteries

Tin-based materials have attracted intensive attention as promising high-capacity anodes for both lithium-ion batteries (LIBs) and sodium-ion batteries (SIBs). However, they suffer from serious capacity fading owing to the inherent huge volume changes and sluggish kinetics. Herein, we propose a facile and scalable self-assembly NaCl template-assisted in situ catalytic strategy for preparing monodisperse multicore-shell SnSb@SnOx/SbOx@C nanoparticles (10-30 nm) space-confined in three-dimensional (3D) graphene-like porous carbon networks. In the unique nanostructure, the synergistic effect of Sn and Sb and abundant free space provided by porous carbon network effectively relieves the volume change, the amorphous SnOx/SbOx shell enhances the interface interaction between SnSb and carbon as well as facilitates ion diffusion, the graphitic carbon shells and the 3D graphene-like carbon network with high mechanical flexibility not only inhibits the aggregation and pulverization of SnSb, but also improves the integrity and conductivity of electrode. Thus, the nanocomposite electrode deliver a high specific capacity, superior rate capability (337.3 mAh g(-1) and 244.3 mAh g(-1) at 5 A g(-1) for LIBs and SIBs, respectively), and excellent cycling stability (capacity retention of 93% after 200 cycles at 1 A g(-1) for LIBs; capacity retention of 80% after 500 cycles at 2 A g(-1) for SIBs). This work provides new strategy for the design and fabrication of nanocomposite with robust interface interaction for electrochemical energy conversion and storage application.