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Highlights • The NiCo 2 O 4 and NiCo 2 O 4 @MnO 2 composites synthesized by a hydrothermal method. • NiCo 2 O 4 @MnO 2 maintained reversible capacities of 1000 mA h g−1 after 100 cycles. • NiCo 2 O 4 @MnO 2 electrodes demonstrated an enhanced rate performance. Abstract 3D flower-like NiCo 2 O 4 and NiCo 2 O 4 @MnO 2 were successfully synthesized via a hydrothermal method. Scanning electron microscopy results illustrated that NiCo 2 O 4 is formed by stacking nanosheets, and after reaction in KMnO 4 solution, MnO 2 were evenly coated on the surface of NiCo 2 O 4 formed flower-like structure. The as-synthesized materials were evaluated as an anode materials for lithium-ion batteries, NiCo 2 O 4 and NiCo 2 O 4 @MnO 2 exhibited high specific capacities of 841.9 and 1 000 mA h g−1 after 100 cycles respectively. Moreover, NiCo 2 O 4 @MnO 2 composites demonstrate good rate performance. These enhanced electrochemical properties could be attributed to the distinctive 3D flower-like structure, which increases the contact area between the electrolyte and electrode material to provide more active sites, and reduced volume effects during repeated insertion/extraction of lithium ions. The results suggest that the NiCo 2 O 4 @MnO 2 composites could be promising LIBs anode materials. [ABSTRACT FROM AUTHOR]

Abstract: Composite Li2SnO3/C with good cycle performance for lithium-ion batteries was synthesized by a hydrothermal route. The structure, morphology and electrochemical properties of the as-prepared materials were characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS), thermal gravimetric analysis (TGA) and electrochemical measurements. Results show that the length of the Li2SnO3 nanorods are in the range of 40–60nm while the average diameter is approximately 30nm. Amorphous carbons are distributed among the Li2SnO3 nanoparticles. The first discharge–charge capacities of Li2SnO3/C are 2045.8mAhg−1 and 1756.6mAhg−1. After the 50th cycles, the capacity retained is 598.3mAhg−1 at a constant current density of 60mAg−1 in the voltage range of 0.05–2.0V. The composite Li2SnO3/C exhibits a better electrochemical property than Li2SnO3. [Copyright &y& Elsevier]