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Abstract: In this work, the oxygen‐vacancy abundant NiCo2O4 grown on the N‐doped carbon nanosheets are designed and fabricated through a facile procedure. The obtained special structure combined with the oxygen vacancies effectively enhance the contact area, keep the structural integrity as well as accelerate the electron and lithium ion transfer. As an anode for lithium ion batteries, the special architecture exhibits good cycle stability (1096 mAh g−1 after 100 cycles at current density of 200 mA g−1) and long cycle capability at high current rate (398 mAh g−1 after 500 cycles at 5000 mA g−1). The advantageous features by constructing oxygen‐vacancy abundant transition metal oxides with the conductive N‐doped carbon nanosheets may pave the way for improving the electrochemical performance. [ABSTRACT FROM AUTHOR]

Copper selenide as an anode for lithium-ion batteries suffers from volume expansion/contraction, while constructing nanostructured copper selenide with other components is considered as an effective strategy. In this work, Cu2−xSe@C@Sb2Se3 nanosheets were fabricated through a two step solvothermal procedure with the assistance of glucose. Such a structure can facilitate the migration rate of Li+, enhance the electrical conductivity, buffer the volume variation and prohibit the aggregation of the electrode. As a result, Cu2−xSe@C@Sb2Se3 exhibits good electrochemical performance with a specific capacity of 341 mA h g−1 after 100 cycles at a current density of 100 mA g−1 and 153 mA h g−1 at a rate of 2000 mA g−1. Such a structural design and synthetic strategy may also be applied to explore other nanocomposites to improve the electrochemical performance. [ABSTRACT FROM AUTHOR]

In this work, we design and synthesize amorphous S-doped NiMoO4 on Fe2O3@C nanorods (Fe2O3@NiMoO4-S) as the anode for high performance lithium-ion batteries. The as-prepared Fe2O3@NiMoO4-S exhibits high reversible capacity (1001 mA h g−1 after 100 cycles at a rate of 0.1 A g−1), excellent cycle performance and superior rate capacity (766 mA h g−1 after 1000 cycles at a high current density of 10 A g−1). This excellent performance is attributed to the unique structural features: the amorphous structure can shorten the lithium ion diffusion path, buffer the volume expansion, and maintain the structural integrity during the Li+ insertion/extraction process. The carbon layer and sulfur doping are able to improve the conductivity. Moreover, the amorphous nature with oxygen vacancies makes it favorable for lithium ion transport. [ABSTRACT FROM AUTHOR]

Transition metal oxides, as one of the most promising anode materials for lithium-ion batteries, often suffer from poor electronic conductivity and serious structural collapse. In this work, oxygen-vacancy-abundant CoFe 2 O 4 and NiFe 2 O 4 deposited on N-doped carbon nanosheets are designed and fabricated through a calcination procedure and a solvothermal strategy using Zn-hexamine coordination frameworks as precursors. The as-prepared NC@CoFe 2 O 4 and NC@NiFe 2 O 4 hybrids display improved cycle performances and rate capacities compared with CoFe 2 O 4 , NiFe 2 O 4 , and Fe 2 O 3 . The enhanced lithium storage performances of NC@CoFe 2 O 4 and NC@NiFe 2 O 4 are attributed to the oxygen vacancies and conductive N-doped carbon nanosheets, which increase the electronic conductivity and electrochemical reaction kinetics. The synthetic process in this work provides a new perspective for designing other high-performance transition metal oxide anodes., (© 2020 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)