Nanocomposite anodes for lithium-ion batteries based on Sno2 on multiwalled carbon nanotubes



In this study, multiwall carbon nanotube (MWCNT) based buckypapers were produced via vacuum filtration techniques. The surfaces of the buckypapers were then coated with tin oxide (SnO2) thin films via radio frequency magnetron sputtering techniques. In order to evaluate the electrochemical performance of SnO2 coated buckypapers, bare SnO2 thin films were also deposited onto stainless steel substrates. Bare SnO2 was deposited on the stainless steel coin and on the functionalized MWCNT buckypapers. The SnO2/MWCNT nanocomposites have shown to exhibit desirable electrochemical performances as the negative electrodes for the lithium-ion batteries. MWCNTs not only suppressed the mechanical degradation of SnO2 and, therefore, provided the composite electrode with excellent capacity retention (>700 mAhg−1 after 100 cycles) but also enhanced the electronic conductivity of the electrodes leading to excellent rate capability. The gradient composition of SnO2 from the surface to the center of the buckypaper in the SnO2/MWCNT nanocomposites has been shown to be critical for mitigating the mechanical degradation of electrodes. A nanocomposite produced at 5% O2 + 95 Ar atmosphere gave the best performance, exhibiting significantly high reversible capacity and excellent cycling ability. The excellent lithium storage and rate capacity performance of gradient composition SnO2/MWCNT core-shell nanocomposites make them promising anode materials for lithium-ion batteries. Copyright © 2013 John Wiley & Sons, Ltd.