Mesoporous hollow nanospheres consisting of carbon coated silica nanoparticles for robust lithium-ion battery anodes.

SiO 2 as lithium ion batteries (LIBs) anode has drawn considerable attentions because of its low cost, high theoretical specific capacity and low discharge potentials but been limited by its low conductivity and electrochemical kinetics, resulting in obvious capacity decay and poor rate performance. Herein, we developed a simple approach to synthesize mesoporous hollow nanosphere (MHSiO 2 @C) assembled by conformal carbon coating tiny silica nanoparticles through chemical polymerization of dopamine inside the shell of MHSiO 2 . The continuous carbon can conformally coat on the surface of all primary SiO 2 nanoparticles in the shell, which not only enhances the conductivity but also improves the structural stability of the MHSiO 2 . Compared to raw MHSiO 2 and non-conformal carbon coated MHSiO 2 , the MHSiO 2 @C demonstrate a high reversible capacity of 440.7 mA h g −1 at a current density of 0.5 A g −1 after 500 cycles and excellent rate performance due to synergetic effect of special structure of MHSiO 2 and carbon conformal coating on each silica nanoparticle. Such a special structure will be a promising platform for LIBs. Significantly, this paper offers a direct evidence to prove the advantage of conformal carbon coating and provides consequentially guide in improving the energy storage performance of low-conductivity oxide based electrode materials. [ABSTRACT FROM AUTHOR]