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SnTe exhibits a layered crystal structure, which enables fast Li-ion diffusion and easy storage, and is considered to be a promising candidate for an advanced anode material. However, its applications are hindered by the large volume variation caused by intercalation/deintercalation during the electrochemical reaction processes. Herein, topological insulator SnTe and carbon nanotubes (CNTs) supported on a graphite (G) carbon framework (SnTe-CNT-G) were prepared as a new, active and robust anode material for high-rate lithium-ion batteries by a scalable ball-milling method. Remarkably, the SnTe-CNT-G composite used as a lithium-ion battery anode offered an excellent reversible capacity of 840 mA h g-1 at 200 mA g-1 after 100 cycles and high initial coulombic efficiencies of 76.0%, and achieved a long-term cycling stability of 669 mA h g-1 at 2 A g-1 after 1400 cycles. The superior electrochemical performance of SnTe-CNT-G is attributed to the stable design of its electrode structure and interesting topological transition of SnTe, combined with multistep conversion and alloying processes. Furthermore, in situ X-ray diffraction and ex situ X-ray photoelectron spectroscopy were employed to study the reaction mechanism. The results presented here provide new insights to design and reveal the reaction mechanisms of transition metal telluride materials in various energy-storage materials.

Metal sulfides are promising lithium-ion battery anode materials with high specific capacities, but there has been little in-depth discussion on the reaction mechanism of metal sulfides. In this study, a robust bimetallic sulfide heterogeneous material (Sb2S3-Co9S8/NC) based on a metal-organic framework was designed. The combination of in situ X-ray diffraction and ex situ transmission electron microscopy revealed the phase evolution behavior during the first cycle. During the lithiation process, Sb2S3 undergoes lithium insertion, conversion and alloying reactions to form crystalline Li2S, Li3Sb and metallic Sb. Co9S8 undergoes lithium insertion and transformation to form metallic Co and Li2S. Lithium ions are extracted from the nanocrystalline phase and transformed into the original Sb2S3 and Co9S8 phases. The Sb2S3-Co9S8/NC anode exhibits excellent cycle stability (616 mA h g-1 at 2 A g-1 after 900 cycles) and fast lithium ion transfer kinetics. These results demonstrate the lithiation/delithiation mechanism of the Sb2S3-based anode and provide a new path for the development of high-performance LIB anodes based on bimetallic sulfides.

Metal sulfides are promising lithium-ion battery anode materials with high specific capacities, but there has been little in-depth discussion on the reaction mechanism of metal sulfides. In this study, a robust bimetallic sulfide heterogeneous material (Sb

SnO2 with high abundance, large theoretical capacity, and nontoxicity is considered to be a promising candidate for use as advanced electrodes. However, the poor electronic conductivity and large volume variations hinder the practical applications of SnO2-based electrodes for use in lithium-ion batteries (LIBs). Herein, the MoS2-SnO2 heterostructures were encapsulated into carbon nanofibers (CNFs) via facile solvothermal and electrospinning methods. Remarkably, when the binder-free and robust MoS2-SnO2@CNF is employed as the anode for LIBs, such a clever structure yields a discharge capacity of 983 mA h g-1 at a current density of 200 mA g-1 after 100 cycles and a capacity of 710 mA h g-1 after 800 cycles at a current density of 2000 mA g-1. Moreover, full cells and flexible full cells were constructed, which exhibited high flexibility and delivered a high reversible capacity of 463 mA h g-1 after 100 cycles at 500 mA g-1. The exceptional performance of MoS2-SnO2@CNF could be attributed to the rational design of the electrode structure. On one hand, the robust structure of the amorphous SnO2 and MoS2 nanoflowers in the conductive carbon network not only provides direct current pathways, but also enhances electron transfer. On the other hand, the abundance of p-n heterogeneous interfaces considerably reduces the charge transfer resistance and enhances the surface reaction kinetics. This work proposes a feasible strategy to enhance the capacity and stability of SnO2-based electrodes and opens up a new avenue for the potential applications of SnO2 anode materials.

The multielectron reaction materials for lithium-ion batteries are interesting charge storage hosts for next-generation high-energy–density anodes. As a class of multiple-anion transition metal compounds (MATMCs), the layered Nickel hydroxide sulfate (NiSH) nanobelts integrate positive-charged cations and intercalated anions, can be expected to construct the advanced high-energy–density materials, but have not yet reported. Herein, the layered NiSH nanobelts grafting on the 3D porous reduced Graphene oxide (rGO) nanosheets were fabricated for the first time as the negative electrode of lithium-ion battery (denoted as NiSH@rGO) by a one-pot hydrothermal approach. As expected, the NiSH@rGO composite delivers a superior initial discharge capacity (1060 mAh g−1 at 200 mA g−1 after 230 cycles) and an exceptional rate capacity (991 mA g−1 at 2000 mA g−1). Through in-situ XRD, ex-situ SEM and TEM, we showed that the outstanding performance of NiSH@rGO anode originate from multielectron reaction mechanism and prominent structural, which render expose more active sites for charge storage, increase the surface wettability of anode, accelerate electron/ion diffusion and ensure the stability of the structure. Above that, it showed excellent lithium storage capacity and high-rate performance. Furthermore, a full cell composed of the NiSH@rGO anode and LiFePO4 cathode displays an impressive capacitance and low-capacity decay rate. Our findings fundamentally and experimentally provide insights into the multi-anionic compounds for markedly enhancing the performance of the multi-electron anodes for advanced high-capacity lithium-ion battery.

Correction for 'MoS

SnO

The development of electrode materials with the synergistic effects of good chemical stability and high electrical conductivity has improved the sluggish ion kinetics and severe capacity degradation of rechargeable lithium batteries. Herein, a multifunctional heterostructure material (MoS3-Ti3C2Tx) comprising a functionalized MXene (Ti3C2Tx) and amorphous MoS3 is prepared by a scalable electrostatic self-assembly method. Remarkably, as lithium-ion battery anodes, the resultant MoS3-Ti3C2Tx not only exhibits increased electrochemical activity, accelerated lithium-ion diffusion and fast charge transfer kinetics but also shows high specific capacity, excellent rate performance and long-term cycling stability. By virtue of these merits, MoS3-Ti3C2Tx offers an excellent reversible capacity of 1043 mAh g−1 at 200 mA g−1 and exhibited a capacity of 568 mAh g−1 at a current density of 2 A g−1 after 1000 cycles. When acting as the cathode for lithium-sulfur batteries, the amorphous MoS3 anchored on MXene demonstrates high capture and catalytic activity towards polysulfide conversion. Accordingly, the optimized electrode exhibits a capacity of 836 mAh g−1 at 0.2C after 100 cycles and a satisfactory rate performance of 463 mAh g−1 at 2C after 400 cycles. Moreover, the associated conversion mechanism is studied by ex situ XPS. These results demonstrate that heterostructure composites constructed by an amorphous sulfide and surface functionalized MXene are feasible electrode materials for both lithium-sulfur batteries and lithium-ion batteries.

Transition metal sulfides have high abundance and large theoretical capacities are considered to be an effective candidate for advanced electrodes of lithium ion batteries (LIBs). Here, a large-scale and controllable method was used in synthesizing ultrathin MoS2 nanosheets anchored on 3D hierarchical nanohybrids with SnS quantum dots, which are decorated on a carbon nanosheet network (MoS2@SnS-QDs/CNN). The 3D cross-linked carbon nanosheet not only could prevent SnS from being directly exposed to the electrolyte but also retained the structural stability of the electrode. Moreover, the MoS2 nanosheets exposed active sites to carry lithium ions. A heterojunction was formed at the interface owing to the close contact between molybdenum disulfide and SnS and greatly increased charge carrying and lithium storage capacities. Benefiting from these structural advantages, the MoS2@SnS-QDs/CNN electrodes showed outstanding electrochemical and long-term cycling performance owing to their unique structures and amazing synergies. As a half-cell anode material, MoS2@SnS-QDs/CNN-2 provided a reversible capacity of 713 mAh g−1 after 1000 cycles at a current density of 2 A g-1. When assembled into a full battery, it still provided 491 mAh g-1 at a current density of 1 A g-1 after 100 cycles. At the same time, a small LED bulb was lit for a while. This advanced material has great potential in other applications, such as supercapacitors, catalysis, and sensors.

Correction for ‘MoS2 nanoflowers encapsulated into carbon nanofibers containing amorphous SnO2 as an anode for lithium-ion batteries’ by Huanhui Chen et al., Nanoscale, 2019, 11, 16253–16261.