Ultrathin alumina-coated carbon nanotubes as an anode for high capacity Li-ion batteries

Alumina-coated carbon nanotubes (CNTs) were synthesized on a copper substrate and have been used as an anode in Li-ion batteries. CNTs were grown directly on the copper current collector by chemical vapor deposition and an ultrathin layer of alumina was deposited on the CNTs by atomic layer deposition, thus forming the binder-free electrode for the Li-ion battery. While CNTs, which form the core of the structure, provide excellent conductivity, structural integrity and Li-ion intercalation ability, the aluminium oxide coating provides additional stability to the electrode, with further enhancement of capacity. The anode showed very high specific capacity, good capacity retention ability and excellent rate capability. This novel anode may be considered as an advanced anode for future Li-ion batteries.This research was supported by World Class University (WCU) program through Korea Science and Engineering Foundation funded by the Ministry of Education, Science and Technology (R31-2008-000-10092). I.L. acknowledges financial support from Doctoral Evidence Acquisition Fellowship and Dissertation Year Fellowship, awarded by University Graduate School, FIU. I.L. also thanks Dr K.W. Jones, Director, AMERI, FIU and Mr Neal Ricks, Manager, Nano- fabrication Facility, AMERI, FIU for AMERI research facilities and Dr Saxena for permitting to use Raman facilities