Highly reversible lithium storage in uniform Li4Ti5O12/carbon hybrid nanowebs as anode material for lithium-ion batteries
Very large area, uniform Li4Ti5O12/carbon composite nanowebs consisting of interconnected nanofibers were synthesized by a simple method based on thermal pyrolysis and oxidation of a composite of electrospun lithium-titanium/polyacrylonitrile nanowebs in argon atmosphere. This novel composite is characterized by the encapsulation of highly uniform nanoscale Li4Ti5O12 crystals in the porous cotton-like carbon matrix. This unique structure, consisting of ultra-small crystals in carbon core/shell architecture, is also characterized by high porosity, with many nanopores and mesopores in the composite, and this, together with the high conductive carbon matrix, would facilitate the excellent electrochemical performance of Li4Ti5O12/carbon composite nanoweb electrode. The Li4Ti5O12/carbon hybrid nanoweb electrodes display a reversible capacity of approximately 160.8 mAhg-1 at a current density of 30 mAg-1 and excellent cycling stability. The Li4Ti5O12/carbon hybrid nanoweb electrodes also exhibit excellent rate performance, delivering a discharge capacity of over 87 mAhg-1 at a current density of 3000 mAg-1. These results indicate that the composite is a promising anode candidate for lithium ion batteries. 2013 Elsevier Ltd.