Multidimensional Synergistic Nanoarchitecture Exhibiting Highly Stable and Ultrafast Sodium-Ion Storage

Conversion-type anodes with multielectron reactions are beneficial for achieving a high capacity in sodium-ion batteries. Enhancing the electron/ion conductivity and structural stability are two key challenges in the development of high-performance sodium storage. Herein, a novel multidimensionally assembled nanoarchitecture is presented, which consists of V2O3 nanoparticles embedded in amorphous carbon nanotubes that are then coassembled within a reduced graphene oxide (rGO) network, this materials is denoted V2O3 subset of C-NTs subset of rGO. The selective insertion and multiphase conversion mechanism of V2O3 in sodium-ion storage is systematically demonstrated for the first time. Importantly, the naturally integrated advantages of each subunit synergistically provide a robust structure and rapid electron/ion transport, as confirmed by in situ and ex situ transmission electron microscopy experiments and kinetic analysis. Benefiting from the synergistic effects, the V2O3 subset of C-NTs subset of rGO anode delivers an ultralong cycle life (72.3% at 5 A g(-1) after 15 000 cycles) and an ultrahigh rate capability (165 mAh g(-1) at 20 A g(-1), approximate to 30 s per charge/discharge). The synergistic design of the multidimensionally assembled nanoarchitecture produces superior advantages in energy storage.