Highly uniform nitrogen-doped carbon decorated MoO2 nanopopcorns as anode for high-performance lithium/sodium-ion storage

[Display omitted] •Highly uniform nitrogen-doped carbon decorated MoO2 nanopopcorns as anode for lithium/sodium-ion storage.•The facile synthesis involves self-templated solvothermal, double-annealing treatment and in-situ pyrolysis of polypyrrole.•The N-doped carbon shell confines MoO2 nanopopcorns with high structural integrity and electrical conductivity. Molybdenum dioxides (MoO2) featuring low cost and high theoretical capacity endow them competitive anode materials for lithium-ion batteries (LIBs)/sodium-ion batteries (SIBs). However, the low electrical conductivity and severe volume expansion occurring during the ion insertion/extraction process hamper their practical application. Herein, a novel dual-annealing design has been developed for the synthesis of highly uniform MoO2 nanopopcorns decorated with nitrogen-doped carbon shell (MoO2/NC). Owing to the unique structural characteristics and vital amorphous NC component, the MoO2/NC nanopopcorn hybrid composite exhibits stabilized charge storage capacity of 1073 mAh g−1 after 200 cycles for LIBs, while 301 mAh g−1 after 500 cycles for SIBs at 0.5 A g−1. Furthermore, when the current density increases to 5 A g−1, the specific capacity could still maintain 630 mAh g−1 and 174 mAh g−1 for LIBs and SIBs, respectively, which disclose the outstanding rate capability of MoO2/NC nanopopcorn anode.