SnO2 coated carbon nanospheres: Facile preparation and electrochemical performances as anode materials for lithium ion batteries

Abstract

In this work, the SnO2/C nanocomposites as the anode material for lithium ion batteries (LIBs) were successfully prepared by ultrasonic dispersing of the hydrothermally-synthesized carbon nanospheres in SnCl2 solution and aging for a period of time and then calcination of the dried intermediates in an inert atmosphere. As demonstrated by the experimental results, the obtained SnO2/C nanocomposites were composed of SnO2 nanocrystals (∼10 nm) coated uniformly on the surface of amorphous carbon nanospheres with diameters ranging from 200 nm to 240 nm. The electrochemical test results show that the prepared SnO2/C nanocomposites exhibited higher reversible capacity than the carbon nanospheres, and better cycling performance than the SnO2 nanocrystals. The enhanced electrochemical performance of SnO2/C nanocomposites could be due to the fact that the coupling of SnO2 nanocrystals and carbon nanospheres could not only effectively improve the mobility of charge carriers, but also effectively inhibit the collapse of the SnO2 structure at the expense of a part of the capacity, thus resulting in better structural stability of the SnO2/C nanocomposites.