SnCo@C@Mn₃O₄ Yolk–Shell Hierarchical Hybrid Nanocubes with Exceptional Lithium Storage Performance

Abstract

SnCo@C@Mn3O4 yolk–shell hierarchical hybrid nanocubes are successfully fabricated via the thermal reduction of CoSn­(OH)6@polydopamine and the subsequent surface-coating of Mn3O4 nanoparticles on the carbon layer. In the novel yolk–shelled nanostructures, the multiple SnCo alloy nanocores decrease the size of alloy nanoparticles and provide sufficient sites for the lithiation of Sn. Simultaneously, N-doped carbon as the intermediate layer prevents the agglomeration between SnCo and Mn3O4 nanoparticles and thus improves their structural stability. More importantly, Mn3O4 nanoparticles reinforce the carbon shell of yolk–shell nanostructures while decreasing the carbon content, resulting in high capacity and outstanding cyclic stability of SnCo@C@Mn3O4 nanocubes. With the respective advantages of three nanocomponents and their synthetic effects, SnCo@C@Mn3O4 yolk–shell hierarchical hybrid nanocubes show impressive reversible capacity (999 mAh g–1 at 0.1A g–1 after 300 cycles) and outstanding high-rate cyclic stability (734 mAh g–1 at 0.5A g–1 after 650 cycles). This study provides new insight into the rational design of novel Sn-based nanocomposites for enhanced electrochemical properties.

Insight into the Self-Assembled Three-Dimensional Sandwich-Like Hollow Silicon Nanoarray/Graphene Lithium Storage Architecture by Sonication-Assisted Functionalization

“…The increasing development of technological applications from portable electronics and medical implants to electric vehicles and power storage installations depends upon the high power density of lithium-ion batteries (LIBs). , However, the current commercial graphite-based anodes cannot yet satisfy the increasing need of LIBs in these applications, owing to their low theoretical specific capacity of 372 mAh g –1 . , Therefore, advanced anode materials with higher specific capacities, such as silicon-based, − tin-based, − and other metal-based − materials, have been developed in recent years. Among them, silicon (Si) has been considered as one of the most promising anode materials for next-generation LIBs because of its abundance in nature and being environmental benignity, with a relatively low working potential (∼0.5 V versus Li/Li + ) and a very high theoretical specific capacity of 4200 mAh g –1 , which is over 10 times that of commercial graphite anodes. , However, pure Si anodes suffer from poor electronic conductivity and large volume expansion/contraction (>300%) during Li-ion insertion/extraction.…”