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Copper selenide as an anode for lithium-ion batteries suffers from volume expansion/contraction, while constructing nanostructured copper selenide with other components is considered as an effective strategy. In this work, Cu2−xSe@C@Sb2Se3 nanosheets were fabricated through a two step solvothermal procedure with the assistance of glucose. Such a structure can facilitate the migration rate of Li+, enhance the electrical conductivity, buffer the volume variation and prohibit the aggregation of the electrode. As a result, Cu2−xSe@C@Sb2Se3 exhibits good electrochemical performance with a specific capacity of 341 mA h g−1 after 100 cycles at a current density of 100 mA g−1 and 153 mA h g−1 at a rate of 2000 mA g−1. Such a structural design and synthetic strategy may also be applied to explore other nanocomposites to improve the electrochemical performance. [ABSTRACT FROM AUTHOR]

Metal chalcogenides are considered as promising anode materials for lithium and sodium-ion batteries because of their large theoretical capacities. However, large volume expansion and low conductivity still limit their practical applications. In this work, three-dimensional cube-like Sb2Se3/C assembled by ultrathin nanosheets is prepared by a facile solvothermal method and a carbonization process. The as-achieved cube-like Sb2Se3/C displays good electrochemical performance both in lithium-ion batteries (LIBs) and sodium-ion batteries (SIBs). When applied as anode for LIBs, a capacity of 440.9 mAh g−1 can be maintained after 100 cycles at the current density of 0.2 A g−1. When used as the anode for SIBs, it exhibits the discharge capacity of 433 mAh g−1 at the 100th cycle at 0.2 A g−1. [ABSTRACT FROM AUTHOR]

In this work, we design and synthesize amorphous S-doped NiMoO4 on Fe2O3@C nanorods (Fe2O3@NiMoO4-S) as the anode for high performance lithium-ion batteries. The as-prepared Fe2O3@NiMoO4-S exhibits high reversible capacity (1001 mA h g−1 after 100 cycles at a rate of 0.1 A g−1), excellent cycle performance and superior rate capacity (766 mA h g−1 after 1000 cycles at a high current density of 10 A g−1). This excellent performance is attributed to the unique structural features: the amorphous structure can shorten the lithium ion diffusion path, buffer the volume expansion, and maintain the structural integrity during the Li+ insertion/extraction process. The carbon layer and sulfur doping are able to improve the conductivity. Moreover, the amorphous nature with oxygen vacancies makes it favorable for lithium ion transport. [ABSTRACT FROM AUTHOR]

In this work, one dimensional CNTs@C anchored with Cu2‐xSe nanospheres have been prepared by a facile solvothermal method. The parameters affected the morphology of the sample are investigated. When evaluated as anode for Li ion batteries, the obtained CNTs@C@Cu2‐xSe electrode delivers enhanced electrochemical performance with high reversible capacity, better cycle stability and rate capability. After 100th cycle, a discharge capacity of 399 mAh g−1 can be achieved at 0.1 A g−1. Even at high rate of 2 A g−1, the electrode can still keep a capacity of 198 mAh g−1 after 50 cycles. In addition, the obtained CNTs@C@Cu2‐xSe shows typical faradaic redox properties and exhibits excellent specific capacity (302.7 g−1 at 1 A g−1) and prominent cycling stability (86.9 % capacity retention after 2000 cycles at 2 A g−1). The enhanced electrochemical performance can be attributed to the unique structure. The Cu2‐xSe nanospheres consist of numerous nanocrystalline, which increases the contact area between Cu2‐xSe and electrolyte, reduces the pave length as well as accommodates volume change during cycling. The amorphous carbon layer with numerous carboxyl and hydroxyl groups strengthens the adhesion between the Cu2‐xSe and the CNTs. And the CNTs can enhance the conductivity of Cu2‐xSe and alleviate the mechanical stress and strain of the electrode during charge and discharge process. Polycrystalline Cu2‐xSe nanospheres anchored onto CNTs@C have been prepared through solvothermal method. Such unique structure is beneficial for improving the electrochemical performance. [ABSTRACT FROM AUTHOR]

Porous CeB6 nanostructure was successfully synthesized at 700 °C for 2 h under argon atmosphere by a melt-assisted method using CeCl3 and NaBH4 as reactants, NaCl-KCl as reaction melt. The obtained product was characterized by X-ray diffraction (XRD), Raman spectroscopy, scanning electron microscopy (SEM), transmission electron microscopy (TEM), and Brunauer-Emmett-Teller (BET) method. XRD pattern and Raman spectrum confirmed the formation of CeB6 with high purity. SEM and TEM results showed CeB6 powder had a mesopore structure and consisted of nanoparticles with mean size of ~ 8 nm. Porous CeB6 had high surface area of 64.14 m2 g−1 and pore volume was 0.132 cm3 g−1. Adsorption property of porous CeB6 for methylene blue was also evaluated. The results displayed that adsorption efficiency of 80% on porous CeB6 can be realized rapidly within 10 min with adsorption capacity of 6.75 mg/g. Repeatability test showed that porous CeB6 had the potential to be a reusable adsorbent for MB rapid removal. [ABSTRACT FROM AUTHOR]

In this work, we develop a facile solvothermal method, sintering process as well as an in situ chemical polymerization route to efficiently fabricate hierarchical snowflake like ZnCo2O4-xF2x/polypyrrole composite. According to the electron microscope observations, the formation mechanism is proposed as an aggregation process and anisotropic growth mechanism. In favor of the element doping and the structural advantages, the ZnCo2O4-xF2x/polypyrrole composites display excellent electrochemical performance including a high reversible capacity, excellent cyclic ability, and good rate behavior. The excellent electrochemical performance is attributed to the synergistic effect of the mesoporous structure, F anions doping and coating of PPy layer, which shortens the diffusion path for the Li+ ions, improves the kinetic process, promotes the electron transfer on the electrode/electrolyte interface and buffers the volume change during Li+ ion insertion/extraction process. [ABSTRACT FROM AUTHOR]

Erythrocyte like MnCo2O4 has been synthesized using a facile solvothermal method and sintering treatment. The obtained sample is constructed by many smaller nanocrystals and possesses high surface area, which can efficiently increase the contact area for electrode/electrolyte, shorten the pathway for Li+ diffusion and buffer the volume variation during electrochemical cycling. Electrochemical investigations demonstrate that the erythrocyte like MnCo2O4 exhibits good electrochemical performance. A specific capacity of 960 mAh g−1 can be achieved after 100 cycles at the current density of 200 mA g−1. [ABSTRACT FROM AUTHOR]

Ternary metal oxides are considered as promising anode materials for lithium-ion batteries (LIBs), because they can circumvent the shortcomings of single-component oxides. Herein, a facile hydrothermal route combined with calcination is used to fabricate manganese cobalt oxide (MnCo2O4) hollow spheres comprised of many mesoporous nanosheets. When used as anode material, the MnCo2O4 hollow spheres display excellent electrochemical properties. A specific capacity of 1023 mAh g−1 can be achieved after 200 cycles at a current density of 200 mA g−1. Even at a high current density of 5000 mA g−1, a reversible discharge capacity as high as 755 mAh g−1 can be achieved. [ABSTRACT FROM AUTHOR]