Improved Li storage performance in SnO2 nanocrystals by a synergetic doping

Abstract

Tin dioxide (SnO is a widely investigated lithium (Li) storage material because of its easy preparation, two-step storage mechanism and high specific capacity for lithium-ion batteries (LIBs). In this contribution, a phase-pure cobalt-doped SnO(Co/SnO and a cobalt and nitrogen co-doped SnO2(Co-N/SnO2 nanocrystals are prepared to explore their Li storage behaviors. It is found that the morphology, specific surface area, and electrochemical properties could be largely modulated in the doped and co-doped SnOnanocrystals. Gavalnostatic cycling results indicate that the Co-N/SnOelectrode delivers a specific capacity as high as 716 mAh g â'1 after 50 cycles, and the same outstanding rate performance can be observed in subsequent cycles due to the ionic/electronic conductivity enhancement by co-doping effect. Further, microstructure observation indicates the existence of intermediate phase of Li 3 N with high ionic conductivity upon cycling, which probably accounts for the improvements of Co-N/SnOelectrodes. The method of synergetic doping into SnOwith Co and N, with which the electrochemical performances is enhanced remarkably, undoubtedly, will have an important influence on the material itself and community of LIBs as well.