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Sb‐based oxides electrodes have received tremendous attention owing to their high theoretical capacities and electrochemical activities. However, the huge volume change during ion insertion/extraction process and poor electronic conductivity limit their wide applications in the electrochemical energy storage. In this study, SbO2/Sb2O3 nanoparticles embedded in N‐doped carbon fibers are successfully synthesized. The composite can display a high reversible specific capacity of 622 mAh g−1 for lithium‐ion batteries and a desirable reversible capacity 307 mAh g−1 for sodium‐ion batteries at current density of 100 mA g−1. Such superior lithium and sodium storage performance can be ascribed to that carbon fibers can effectively restrict the large volume change and enhance the electrochemical stability. [ABSTRACT FROM AUTHOR]

Due to its high electrochemical activities and low intercalation potential for Li/Li+, transition metal phosphides (TMPs) are booming as commerciogenic anode for lithium‐ion batteries (LIBs). Herein, the reasonable devise of nitrogen‐doped carbon‐coated CoP (CoP@NC) nanocomposites, which is derived from metal–organic frameworks (MOF‐Co) precursors, combining with graphene modification, is presented. The ultrafine CoP@NC nanoparticles are strongly incorporated with graphene networks (CoP@NC/GO). When assessed as anode electrode for LIBs, novel dual carbon encapsulation architectures of CoP@NC/GO hybrid composites exhibit superior cyclability (345 mAh g−1 at 1500 mA g−1 after 1000 cycles) and prominent rate ability (404 mAh g−1 at 3000 mA g−1). It is believed that this strategy can be helpful for boosting the electrochemical performance of the TMPs family as advance anode materials for energy storage systems. [ABSTRACT FROM AUTHOR]

Metal selenides have been widely studied as anodes for lithium‐ion batteries, owing to the excellent electrochemical performance. However, the large volume change and poor conductivity may lead to unsatisfactory cycling stability and rate capability. Herein, the FeSe2/carbon matrix nanoparticles embedded into N‐doped graphene sheets (NGS) are designed and synthesized through a two‐step method. When employed as anodes for lithium‐ion batteries, the FeSe2/C@NGS composites exhibit high reversible specific capacities and excellent cycling stabilities of 757.0 mAh g−1 after 100 cycles at 100 mA g−1 and 593.8 mAh g−1 after 1000 cycles at 2000 mA g−1. The carbon matrix and NGS construct binary conductive networks, which not only improve the inner conductivity of FeSe2 and conductivity between FeSe2/C nanoparticles, but also provide elastic buffer space to sustain the structural strain and accommodate the volume expansion and contraction of electrodes during the discharge and charge process. Furthermore, the reversible redox reaction of FeSe2 involves the formation of Fe and Li2Se during the cycling process. This work may open a new avenue for electrode material synthesis methodologies using metal‐organic frameworks as a template and to explore the lithium storage mechanisms of metal selenides for next‐generation batteries. [ABSTRACT FROM AUTHOR]