Porous Hollow Superlattice NiMn2O4/NiCo2O4 Mesocrystals as a Highly Reversible Anode Material for Lithium-Ion Batteries

A Hierarchical SnO2@Ni6MnO8 Composite for High-Capacity Lithium-Ion Batteries

Semiconductor-based composites are potential anodes for Li-ion batteries, owing to their high theoretical capacity and low cost. However, low stability induced by large volumetric change in cycling restricts the applications of such composites. Here, a hierarchical SnO2@Ni6MnO8 composite comprising Ni6MnO8 nanoflakes growing on the surface of a three-dimensional (3D) SnO2 is developed by a hydrothermal synthesis method, achieving good electrochemical performance as a Li-ion battery anode. The composite provides spaces to buffer volume expansion, its hierarchical profile benefits the fast transport of Li+ ions and electrons, and the Ni6MnO8 coating on SnO2 improves conductivity. Compared to SnO2, the Ni6MnO8 coating significantly enhances the discharge capacity and stability. The SnO2@Ni6MnO8 anode displays 1030 mAh g-1 at 0.1 A g-1 and exhibits 800 mAh g-1 under 0.5 A g-1, along with high Coulombic efficiency of 95%. Furthermore, stable rate performance can be achieved, indicating promising applications.

Preparation of ultrathin carbon-coated CdS nanobelts for advanced Li and Na storage

In this paper, we report a simple hydrothermal method for preparation of ultrathin carbon-coated CdS (CdS@C) nanobelts. The CdS@C nanobelts show superior electrochemical properties as an anode material for Li-ion batteries. The optimized CdS@C composites deliver a reversible capacity around 910 mAhg^-1 and 48 mAhg^-1 at 0.1 Ag^-1 and 30.0 Ag^-1, respectively. Moreover, the optimized nanobelts are also potential materials for Na storage. A stable capacity around 240 mAhg^-1 is obtained at 0.1 Ag^-1, even after 100 cycles.

Sintering Temperature Induced Evolution of Microstructures and Enhanced Electrochemical Performances: Sol-Gel Derived LiFe(MoO4)2 Microcrystals as a Promising Anode Material for Lithium-Ion Batteries

A facile sol-gel process was used for synthesis of LiFe(MoO₄)₂ microcrystals. The effects of sintering temperature on the microstructures and electrochemical performances of the as-synthesized samples were systematically investigated through XRD, SEM and electrochemical performance characterization. When sintered at 650°C, the obtained LiFe(MoO₄)₂ microcrystals show regular shape and uniform size distribution with mean size of 1–2 μm. At the lower temperature (600°C), the obtained LiFe(MoO₄)₂ microcrystals possess relative inferior crystallinity, irregular morphology and vague grain boundary. At the higher temperatures (680 and 700°C), the obtained LiFe(MoO₄)₂ microcrystals are larger and thicker particles. The electrochemical results demonstrate that the optimized LiFe(MoO₄)₂ microcrystals (650°C) can deliver a high discharge specific capacity of 925 mAh g⁻¹ even at a current rate of 1 C (1,050 mA g⁻¹) after 500 cycles. Our work can provide a good guidance for the controllable synthesis of other transition metal NASICON-type electrode materials.