Embedding Sb6O13 in three-dimensional honeycomb-like holey graphene network for superior lithium storage

Antimony oxides are of great promise for lithium storage due to their high theoretical capacity, but low intrinsic conductivity and large volume change during lithium-ion insertion/extraction lead to inferior cycling stability. Herein, Sb6O13 nanocrystals were successfully embedded in three-dimensional (3D) honeycomb-like reduced holey graphene oxides (HrGO) sheets by H2O2-assisted solvothermal method, and the as-synthesized Sb6O13/HrGO composite was demonstrated to deliver superior electrochemical lithium-storage performance. During the preparation process, graphene oxides (GO) sheets were pretreated with H2O2 to boost formation of in-plane nanoholes, which play crucial roles in both constructing Sb6O13/HrGO with unique 3D honeycomb-like structure and boosting lithium-storage kinetics. 3D interconnect HrGO sheets with honeycomb-like structure construct a stereoscopic conductive network skeleton for fast electron transfer and alleviating volume expansion of active components during charging/discharging process. Moreover, abundant in-plane nanoholes enable lithium ions to migrate cross graphene sheets, resulting in shortening diffusion distance and fastening diffusion kinetics. Thus, Sb6O13/HrGO electrode exhibited a high reversible capacity of 956.1 mA h g−1 (200 mA g−1) based on conversion-alloying mechanism and superior high-rate capability (493.4 mA h g−1 at 1000 mA g−1) for lithium storage. This work provides a facile, environmental-friendly and scalable strategy to fabricate composites with special structures for high-rate energy storage.