Encapsulation of SnO2 nanoparticles into hollow TiO2 nanowires as high performance anode materials for lithium ion batteries

In this work, a new nanostructure of SnO2 nanoparticles (NPs) encapsulated into hollow TiO2 nanowires (SnO2@TiO2) has been successfully fabricated. This unique architecture intrinsically possess void space in between the TiO2 shell and SnO2 nanoparticle cores, as confirmed by XRD, XPS, SEM, TEM and HRTEM characterizations. The TiO2 shell of the composite can not only alleviate the pulverization and drastic volume change of the SnO2 NPs and maintain the structural integrity, but also contribute to the total capacity of the composite. Moreover, the void space can also accommodate the volume expansion of SnO2 and provide highly efficient channels for the fast transport of both electrons and lithium ion during discharge/charge cycling process. When tested as potential anode materials for lithium ion batteries, the as-prepared hollow TiO2 nanowires shell encapsulating SnO2 NPs architecture exhibits good lithium storage performance and excellent cyclability (which delivers a higher reversible capacity of 445 mAh g(-1) at 800 mA g(-1) after 500 cycles). The unique architecture should be responsible for the superior electrochemical performance. (C) 2013 Elsevier B.V. All rights reserved.