Hierarchical nanocomposite of hollow carbon spheres encapsulating nano-MoO₂ for high-rate and durable Li-ion storage

As a new class of promising anode materials for Li-ion batteries, the application of transition metal oxides is hindered by poor electrochemical utilization and stability. In this work, we report a unique hollow structure of carbon-encapsulated MoO₂ nanospheres as a high-rate and durable anode material for Li-ion batteries. Three-dimensional hierarchically porous carbon hollow nanospheres provide a universal and open framework for encapsulating MoO₂ nanodeposits by a facile impregnation-calcination approach. The hybrid architecture is of great benefit in fast and stable Li-ion storage by shortening Li-ion and electron transport pathways, increasing electronic conductivity, and buffering volume fluctuation upon cycling. The electrochemical advantages bestow the MoO₂/C nanocomposite with an outstanding specific capacity of 1051 mAh g⁻¹ at 0.1 A g⁻¹, superb rate capability (701 mAh g⁻¹ at 2 A g⁻¹) and excellent cycling stability. The present study demonstrates the promising use of hollow-structured MoO₂/C nanocomposites for high performance Li-ion batteries.