Materials Research Bulletin, Vol.70, 456-460, 2015
Octahedral core-shell cuprous oxide/carbon with enhanced electrochemical activity and stability as anode for lithium ion batteries
Core-shell Cu2O/C octahedrons are synthesized by a simple hydrothermal method with the help of carbonization of glucose, which reduces Cu(II) to Cu(I) at low temperature and further forms carbon shell coating at high temperature. SEM and TEM images indicate that the carbon shell is amorphous with thickness of similar to 20 nm wrapping the Cu2O octahedral core perfectly. As anode of lithium ion batteries, the core-shell Cu2O/C composite exhibits high and stable columbic efficiency (98%) as well as a reversible capacity of 400 mAh g(-1) after 80 cycles. The improved electrochemical performance is attributed to the novel core-shell structure, in which the carbon shell reduces the electrode polarization and promotes the charge transfer at active material/electrolyte interface, and also acts as a stabilizer to keep the octahedral structure integrity during discharge-charge processes. (C) 2015 Elsevier Ltd. All rights reserved.