Synthesis of SnO2/Transition Metal Oxide Hollow Nanospheres and Their Electrochemical Properties As Anode for Li-Ion Battery
In this study, we synthesized multi-layered hollow spheres, composed of SnO2 and transition metal oxides (Co3O4 and Fe2O3), by a simple sol-gel based process. Even though cobalt (Co) is well-known catalyst metal for the reversible reaction of Li2O, it is one of expensive materials. So, we also synthesize the SnO2@Fe2O3 hollow spheres with the similar synthesis procedure. The size of synthesized SnO2 hollow sphere is about 60 nm and the shell thickness is about 5 nm. After Co3O4 and Fe2O3 coating, the size was not significantly changed (Fig. 1). The SnO2@Co3O4 and SnO2@Fe2O3@C electrodes showed much higher reversible capacity than SnO2 hollow sphere electrode (Fig. 2) and further cycling test is also examined. The synergistic effects between SnO2/Co3O4 (Fe2O3) and the reaction mechanism observed by TEM and electrochemical analyses will be discussed in this presentation. Furthermore, we also prepared various electrodes such as commercial SnO2 nanopowder, SnO2@C hollow spheres, SnO2@ Fe2O3@C solid spheres and the electrochemical performances will be compared. We believe that our studies might suggest the design strategy for the next-generation LIBs, and it can be applied to other SnO2-metal oxides composites.
Fig. 1 SEM images of (a) SnO2@Co3O4 hollow spheres and (b) SnO2@Fe2O3 hollow spheres.
Fig. 2 Cycling performance of SnO2, Co3O4/SnO2, and SnO2@Fe2O3@C hollow sphere electrodes.
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