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Because of their large volume variation and inferior electrical conductivity, Mn3O4-based oxide anode materials have short cyclic lives and poor rate capability, which obstructs their development. In this study, we successfully prepared a Mn3O4/N-doped honeycomb carbon composite using a smart and facile synthetic method. The Mn3O4 nanopolyhedra are grown on N-doped honeycomb carbon, which evidently mitigates the volume change in the charging and discharging processes but also improves the electrochemical reaction kinetics. More importantly, the Mn—O—C bond in the Mn3O4/N-doped honeycomb carbon composite benefits electrochemical reversibility. These features of the Mn3O4/N-doped honeycomb carbon (NHC) composite are responsible for its superior electrochemical performance. When used for Li-ion batteries, the Mn3O4/N-doped honeycomb carbon anode exhibits a high reversible capacity of 598 mAh·g−1 after 350 cycles at 1 A·g−1. Even at 2 A·g−1, the Mn3O4/NHC anode still delivers a high capacity of 472 mAh·g−1. This work provides a new prospect for synthesizing and developing manganese-based oxide materials for energy storage. [ABSTRACT FROM AUTHOR]

Hierarchical Li 4 Ti 5 O 12 -TiO 2 microspheres are synthesized via an oil/water interface method with the assistance of cetyltrimethylammonium bromide (CTAB) and following calcination. The as-prepared Li 4 Ti 5 O 12 -TiO 2 microspheres are consisted of nanoflakes ( ca. 15 nm in thickness); moreover, Li 4 Ti 5 O 12 and anatase TiO 2 in the nanoflake building blocks are bounded by (011) and (001) facets, respectively. More especially, it is found that CTAB plays a very important role in the phase and morphology of the Li 4 Ti 5 O 12 -TiO 2 composite. When employed as the anode materials for lithium-ion batteries, the Li 4 Ti 5 O 12 -TiO 2 microspheres show initial discharge capacities of 234, 170, 151 and 140 mAh g −1 at charge/discharge rate of 1, 5, 10, and 20C, respectively; furthermore, after 100 cycles at 5C, the discharge capacity remains at 158 mAh g −1 with a capacity retention of 92.9%. The excellent electrochemical properties of the product can be ascribed to the synergistic effect of the exposed Li 4 Ti 5 O 12 (011) and anatase TiO 2 (001) facets, abundant phase interfaces, hierarchical structures, and thin flake-like building blocks. [ABSTRACT FROM AUTHOR]

F-doped V 2 O 3 nanoparticles/N-doped carbon composite was initially synthesized and applied as a high-rate anode material for LIBs. [Display omitted] • F-doped V 2 O 3 /N-doped carbon composite is prepared for the first time. • Doping F and combined with NC bring fast electrochemical reaction kinetics. • F-V 2 O 3 /NC anode shows excellent rate performance and cyclic stability. • High capacity of 481 mA h/g is achieved at 2 A/g. The development and application of V 2 O 3 -based anodes are hindered by their poor reversible capacity and rate performance. Doping F and combined with N-doped carbon at the same time would achieve excellent electrochemical performance, but the related materials are not prepared and employed to lithium-ion batteries due to the absent synthetic method. In this investigation, a simple strategy was firstly invented to achieve F-doped V 2 O 3 /N-doped carbon composite. The F-doped V 2 O 3 nanoparticles are adhered to N-doped carbon, which would enhance electrochemical reaction kinetics. As a result, a high capacity of 481 mAh/g can be obtained at 2 A/g. [ABSTRACT FROM AUTHOR]

Spinel oxide anode materials are hardly used for commercial lithium-ion batteries because of their evident volume expansion in the discharging process and poor electronic conduction. Preparing a composite material of nanostructured spinel bimetallic oxides and carbon will solve the above problems and achieve outstanding electrochemical performance. In this study, an ultrafast approach (only 10 min) to synthesize spinel AMn 2 O 4 (A= Co, Mn, Zn) nanopolyhedras and their composites with GO was successfully developed. Integrating spinel CoMn 2 O 4 nanopolyhedras with GO can profoundly inhibit the problem of volume expansion but also eminently upgrading conductivity. The CoMn 2 O 4 /GO composite anode displays competent cyclic life and rate capability for lithium ion battery, delivering a large capacity of 738 mAh g−1 after 340 cycles at 2 A g−1. The ultrafast approach and alluring electrochemical performance of this work will inevitably give impetus to the fast development and application of spinel oxides. [Display omitted] • Spinel CoMn 2 O 4 and CoMn 2 O 4 /GO were synthesized by an ultrafast method. • The ultrafast synthetic method can be expanded to other spinel oxides. • Nanopolyhedras grown on GO leads to the alluring electrochemical performance. • High capacity of 738 mA h g−1 after 340 cycles is achieved at 2 A g−1. [ABSTRACT FROM AUTHOR]

• Ni 2 VO 4 and Ni 2 V 4 O/AB composite are prepared for the first time. • Ni 2 VO 4 and Ni 2 V 4 O/AB composite is initially used as an anode for LIBs. • The size of Ni 2 VO 4 nanoparticles is ultrasmall. • High capacity of 511 mA h g−1 after 350 cycles is achieved at 1 A g−1. Spinel nickel vanadate has not been synthesized and applied to anode for lithium-ion batteries on account of the missing synthetic route. In the study, a simple route is created to obtain a new spinel Ni 2 VO 4 /acetylene black composite. The obtained Ni 2 VO 4 nanoparticles are ultrasmall and anchored on acetylene black, which could markedly mitigate the volume alteration and elevate electrochemical reaction kinetics. For this reason, a large reversible capacity of 511 mAh/g was maintained at 350th cycle under 1 A g−1. [ABSTRACT FROM AUTHOR]

Abstract Mesoporous Ti 2 Nb 10 O 29 microspheres are prepared through a solvothermal method in isopropanol-glycerol solvent followed by calcination treatment. The Ti 2 Nb 10 O 29 microspheres with diameter in the range between 1.0 and 2.0 µm are assembled from nanoparticles. The special hierarchical mesoporous structure of Ti 2 Nb 10 O 29 microspheres can reduce the Li+ ions diffusion distance and supply large interfacial area between electrolyte and electrode, endowing them with better electrochemical properties compared to Ti 2 Nb 10 O 29 nanoparticles. At different current densities of 1, 5, 10, 20 and 30 C, the first discharge capacity of mesoporous microspheres is respectively 268.9, 218.5, 205.3, 180.5, and 158.1 mA h g−1. By contrast, the corresponding values of Ti 2 Nb 10 O 29 nanoparticles are quickly reduced from 254.6, 196.3, 159.4, 127.5, to 99.0 mA h g−1. It worth noting that Ti 2 Nb 10 O 29 microspheres exhibit excellent rate capacities. Furthermore, at a current density of 10 C, the specific capacity of Ti 2 Nb 10 O 29 microspheres can be maintained at 173.5 mA h g−1 after 500 cycles, with 86.8% retention of the first discharge capacity. These results suggest that the Ti 2 Nb 10 O 29 mesoporous microspheres would be developed as potential anodic materials for high performance lithium-ion batteries. [ABSTRACT FROM AUTHOR]

The development of iron nitride anode materials is greatly impeded by their traditional synthetic methods. In this work, carbon encapsulated Fe 3 N nanospheres grown on N-doped porous carbon nanosheet is successfully prepared by a green, facile and controllable approach. Only a small nitrogen source is needed in the synthetic process by in-situ nitrogenization. The Fe 3 N nanospheres are coated by carbon and uniformly adhered to N-doped porous carbon nanosheet, which prominently mitigates the variation of volume and elevates the electrochemical reaction kinetics. The feature is conducive to realizing a long life and brilliant rate performance. As an anode for lithium-ion batteries, a high discharge capacity of 484 mA h g−1 is delivered after 600 cycles at 2 A g−1. Extensive impact is brought by this study for the preparation and application of metal nitride materials. [Display omitted] • Fe 3 N@C/NPCN composite is prepared by green, facile and controllable route. • Only a small nitrogen source is needed in the synthesis process. • Carbon encapsulated Fe 3 N nanoparticles are uniformly grown on NPCN. • High capacity of 484 mAh g−1 after 600 cycles is achieved at 2 A g−1. [ABSTRACT FROM AUTHOR]