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The layered nickel-cobalt-manganese LiNi1/3Co1/3Mn1/3O2 (LNCM) was investigated as commercializable and high reversible capacity cathode material by more and more investigators in recent years. In this paper, the LiNi1/3Co1/3−xMn1/3YxO2 (x = 0, 0.02, 0.05, 0.10) samples were successfully obtained by a ball milling combined with calcination method. The synthesized LNCM nanocomposites are characterized by different analytical methods. The effect of amount of Y ions doping on the lithium storage performance of LiNi1/3Co1/3Mn1/3O2 was also studied systematically. The Y3+ ions replace the part of Co ions, reducing cation mixing and increasing the diffusion coefficient of Li+ ions in the lattice. It causes the unit cell volume to become larger, and the structure of the material becomes more stable in the intercalation and de-intercalation process of Li+ ions. These test results show that LiNi1/3Co1/3−0.05Mn1/3Y0.05O2 (Y-0.05 LNCM) sample behaves best electrochemical properties with the specific capacity of 174.8 mAh g–1 at 0.5 C after 100 cycles. [ABSTRACT FROM AUTHOR]

Fe3O4 and Fe3O4/NiO heterostructures were successfully prepared by a simple one-step solvothermal method. The morphology of Fe3O4/NiO heterostructures is flower-like spheres composed of nanosheets with a thickness of 10–20 nm. As anode material for lithium-ion batteries (LIBs), the electrochemical performance of the Fe3O4 and Fe3O4/NiO heterostructures are comparatively investigated. At current density of 100 mA g−1, the Fe3O4/NiO heterostructures can maintain 1021 mAh g−1 after 100 cycles. The discharge capacity can still maintain at 500 mAh g−1 and the coulomb efficiency is always stable at 99.6% after 1000 cycles at 1 A g−1. The Fe3O4/NiO heterostructures also have lower impedance and better rate capability, compared with the bare Fe3O4 electrode. Moreover, the electrochemical properties of the Fe3O4/NiO heterostructures can be further improved when the new binder CMC-Li is used. At 100 mA g−1, it can still maintain 1544 mAh g−1 after 100 cycles. These loose-layered nanosheets can effectively alleviate the volume expansion of materials in the process of charge and discharge. Meanwhile, the large surface area can provide more reaction sites. The ultra-thin nanosheet can also reduce the diffusion distance of lithium ions, so that the Fe3O4/NiO heterostructures have excellent performance in lithium-ion batteries. [ABSTRACT FROM AUTHOR]

MoSe2/carbon nanotubes (CNTs) composite was synthesized by a hydrothermal method and followed by annealing in Ar gas using Na2MoO4·2H2O, CN2H4Se, and NH2OH·HCl as reactants in the presence of CNTs. The products were characterized by X-ray diffractometer (XRD) and scanning electron microscopy (SEM). The results show that the introduction of CNTs plays a crucial role in the morphology and electrochemical performance as anode materials for lithium-ion batteries (LIBs) and sodium-ion batteries (SIBs). The MoSe2/CNT electrode exhibits a high reversible capacity of 1140 mAh g−1 and 1014 mAh g−1 at the current density of 100 mA g−1 for LIBs and SIBs, respectively. The MoSe2/CNT electrode exhibits higher capacity, better cycling stability compared with the bare MoSe2. The MoSe2 and MoSe2/CNT composite behave good electrochemical properties may be due to their flower-like nanosheets, well-stacked layers, and 3D CNTs networks. The results suggest that the MoSe2/CNT composite could be a promising anode material for LIB and SIB applications. Moreover, our present work provides a new approach for the fabrication of well-crystalline MoSe2 material and further applications in lithium/sodium storage. [ABSTRACT FROM AUTHOR]

Different amounts of Fe2O3-coated NiMoO4/NiO composites were prepared by solvothermal method following with annealing process. The as-prepared NiMoO4/NiO@Fe2O3 composite exhibits a reversible specific capacity of 1250 mAh g−1 after 150 cycles at a current density of 100 mA g−1 as anode for lithium-ion batteries. It exhibits efficient long-term electrochemical performance and maintains the capacity at about 750 mAh g−1 at a high current density of 500 mA g−1 after 200 cycles. The good electrochemical performance of the NiMoO4/NiO@Fe2O3 composite may be due to its smaller size and the Fe2O3 coating which can restrain its volume collapse during the charge–discharge cycle. This work could provide a promising strategy for enhancing the performance of molybdate-based composite materials for practical application in lithium-ion batteries. [ABSTRACT FROM AUTHOR]

NASICON type Na3V2(PO4)3, as a class of cathode material, have attracted much attention and achieved great success especially in case of sodium-ion battery. Herein, carbon-coated Na3V2(PO4)3 nanoplates are fabricated through a solvothermal method combined with thermal treatment. The nanoplate structure and carbon-coated layer could bring several advantages; for example, the nanoplate structure can provide sufficient specific surface area to contact with electrolyte, leading to easy transmission of sodium ions. In addition, carbon coating could indeed increase the electrode conductivity and simultaneously restrain the volume expansion of Na3V2(PO4)3 electrode material during the intercalation/extraction of Na+ ions. Consequently, the carbon-coated Na3V2(PO4)3 nanoplates exhibit impressive sodium storage performance with a high reversible capacity of 107 mAh g–1 at 1 C after 300 cycles and 91 mAh g–1 at 10 C after 2000 cycles. [ABSTRACT FROM AUTHOR]

The composites of Li3V2(PO4)3/C (noted as LVP/C) and Li3V2(PO4)3-V2O3/C (noted as LVP-V/C) are prepared by a rheological phase reaction (noted as RPR) process for anode material. The synthesized samples are measured by the X-ray diffraction (XRD) technique. The content of the carbon in the composite is detected by the thermogravimetric (TG) analysis. The morphologies of powders are observed by the scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The electrochemical properties of the samples as anode material are tested by the battery testing system. The LVP-V/C composite behaved better electrochemical performances than those of LVP/C as an anode material. The reasons that LVP-V/C behaved outstanding electrochemical properties are discussed also. Based on its electrochemical performances, the LVP-V/C composite may be a potential anode material for rechargeable lithium batteries. [ABSTRACT FROM AUTHOR]

In this paper, NiO, Ni7S6, and different proportions of Ni7S6/NiO hybrids were synthesized by solvothermal method. The crystal structure, valence, and morphology of the prepared samples were characterized by X-ray diffraction, X-ray photoelectron spectroscopy, and scanning electron microscopy. Electrochemical performance of the prepared materials was tested by a series of electrochemical methods. And, the results showed that the electrochemical properties of Ni7S6/NiO composites were superior to those of Ni7S6 and NiO, which may be due to the synergistic effect between Ni7S6 and NiO. Furthermore, Ni7S6/NiO-30% shows the best electrochemical properties among the prepared samples. The electrochemical sensor based on the Ni7S6/NiO-30% has good electrocatalytic behavior for glucose oxidation, with a wide linear range from 0.09 to 3.12 mM, low detection limit (0.3 μM), long-term stability, and considerable reproducibility. Furthermore, it has good selectivity and could be used in human serum samples. Thus, this novel non-enzyme sensor has potential application in glucose detection. [ABSTRACT FROM AUTHOR]

KMn8O16 nanorods were synthesized via a reflux method with MnSO4·H2O and KMnO4 as reactants and SnCl4·5H2O as dopant. The microstructures and morphologies of the KMn8O16 nanorods and Sn4+-doped KMn8O16 nanorods were characterized using XRD, BET, SEM, EDX, and TEM. The electrochemical measurements demonstrated that ion-doped KMn8O16 nanorods (molar ratio of Sn4+ and KMn8O16 is 0.03) presented a much higher reversible discharge capacity (151.4 mAh g−1) and went up to a discharge capacity of 159.1 mAh g−1 after 100 cycles, compared with non-doped KMn8O16 nanorods (129.8 mAh g−1) as cathode materials in lithium-ion battery (LIB). These results demonstrate that the Sn4+ doping on the crystal structure of KMn8O16 can enhance the electrochemical property of material during the charging and discharging process. [ABSTRACT FROM AUTHOR]