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To improve the cycling stability and rate performance of SnO 2 –based anode materials applied in lithium ions batteries (LIBs), SnO 2 /graphene oxide (SnO 2 /GO) composite was synthesized by hydrothermal method. The SnO 2 /GO composite material exhibits much more excellent lithium ions storage capacity and cycling stability. The reversible capacity is 612.2 mAhg −1 with the coulombic efficiency of 98.8%, after 100 cycles. Especially, at a high discharge-charge current density (1000 mAg −1 ), the SnO 2 /GO composite showed an outstanding structure stability and rate performance (204.2 mAhg −1 ). Such excellent performance could be attributed to the existence of GO. With the assistance of GO, the composite material achieves more stable structure and high electron conductivity. [ABSTRACT FROM AUTHOR]

A hybrid of multi-walled carbon nanotubes (MWCNTs) anchored with SnS nanosheets is synthesized through a simple solvothermal method for the first time. Interestingly, SnS can be controllably deposited onto the MWCNTs backbone in the shape of nanosheets or nanoparticles to form two types of SnS/MWCNTs hybrids, SnS NSs/MWCNTs and SnS NPs/MWCNTs. When evaluated as an anode material for lithium-ion batteries, the hybrids exhibit higher lithium storage capacities and better cycling performance compared to pure SnS. It is found that the SnS NSs/MWCNTs hybrid exhibits a large reversible capacity of 620mAhg−1 at a current of 100mAg−1 as an anode material for lithium-ion batteries, which is better than SnS NPs/MWCNTs. The improved performance may be attributed to the ultrathin nanosheet subunits possess short distance for Li+ ions diffusion and large electrode-electrolyte contact area for high Li+ ions flux across the interface. It is believed that the structural design of electrodes demonstrated in this work will have important implications on the fabrication of high-performance electrode materials for lithium-ion batteries. [ABSTRACT FROM AUTHOR]

Abstract A hybrid anode based on SnS x composited with reduced graphene oxide (RGO) is the most promising alternative material for the next generation lithium-ion batteries. In this work, we synthesized a novel amorphous SnS x /RGO (a-SnS x /RGO) by a facile hydrothermal method. A-SnS x /RGO exhibits an excellent lithium-ion storage capacity. After 100 cycles the discharge and charge capacity are 562.5 and 546.6 mAhg−1 at a current density of 100 mAg−1. It also exhibits a superior rate performance. When the current density increased to 1000 mAg−1 the reversible capacity was 357.8 mAhg−1. This superior lithium-ion storage performance is attributed to the amorphous structure and the existence of RGO. The amorphous structure could reduce the volume change effect during the discharge and charge process. Graphene with high specific surface area acted as the frame in composite material and can reduce lithium ions' diffusion length and time. What is the most interesting is the existence of strong coupling effect in A-SnS x /RGO which make the interface reaction more faster and more easier. This amorphous material provide a new way for optimizing the cycling stability and improving the rate performance, which is important for the development of high performance electrode materials [ 1 ]. [ABSTRACT FROM AUTHOR]

Well dispersed core/shell structure Fe nanopowders (FeNPs) produced by high energy ion beam evaporation (HEIBE) are added to polyacrylonitrile/N, N-Dimethylformamide (PAN/DMF) solution containing vegetable oil to prepare Fe/C porous nanofibers (FeCPNFs) by electrospinning as electromagnetic microwave absorption material. The FeCPNFs have 3D cross-linked network structure with low graphitization degree. The permittivity and permeability behaviors of the composites made from FeCPNFs and wax are studied in the frequency range of 2.00–18.00 GHz. Mainly due to impedance matching, electric loss, magnetic loss, attenuation constant and “geometrical effect” the FeCPNFs have good microwave absorption properties. The reflection loss (RL) of FeCPNFs can reach − 56.6 dB at matching frequency (4.96 GHz) and matching thickness (4.29 mm). The RL value can also reach −26.1 dB at 11.68 GHz, and effective absorption bandwidth (RL ≤ − 10.0 dB) is 3.00 GHz with a thickness of 2.00 mm. Moreover, under the matching frequency and matching thickness a good absorption performance (RL ≤ − 15.0 dB) from 2.00 GHz to 18.00 GHz is obtained. [ABSTRACT FROM AUTHOR]

The silicon suboxide (SiO) anode material is considered to be a promising anode material of Lithium-ion batteries (LIBs), because of its high theoretical capacity. However, there are severe problems for SiO, including the huge volume change (200%), the low electrical conductivity and the low first Coulombic efficiency. In order to solve those problems, a ternary composite ((SiO x /G/SnO 2)@C) (G denotes graphite) with carbon coating layer is prepared by ball milling, spray drying and sintering. In the composite, graphite as one part of the active materials, can improve the Coulombic efficiency and control volume change of SiO x. To further restrain the high-volume change of SiO x , the carbon coating layer is designed. In particular, owing to the presence of SnO 2 , a better electrochemical performance for (SiO x /G/SnO 2)@C is obtained. The results show that the first charging capacity of (SiO x /G/SnO 2)@C can reach 382.6 mAh g−1 at current density of 100 mA g−1 and the Coulombic efficiency is improved from 62.2% to 74.9%. After 110 cycles, the charging capacity is 424.6 mAh g−1 and the capacity retention rate is 103.9%. In addition, after 90 cycles of rate performance test, (SiO x /G/SnO 2)@C exhibited the highest capacity retention of 104.7%. [ABSTRACT FROM AUTHOR]