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One-dimensional Na2(TiO)SiO4 (SNTO) nanotubes have been successfully synthesized by a straightforward hydrothermal method with the assistance of cetyltetramethyl ammonium bromide (CTAB). Herein, the influence of the Si/Ti ratio on the morphology or composition of SNTO hollow nanotubes has been investigated, and the result shows that the optimum molar ratio of the optimal morphology is 1 : 1. The prepared samples were first applied as anodes in lithium ion batteries (LIBs) for the time being and superior rate capability, ultralong and stable cycling lifespan performance were obtained. The facile and uniquely designed one-dimensional SNTO nanotube electrodes delivered a high reversible capacity of 121.9 mA h g−1 after 5000 cycles at a high current of 1.0 A g−1 without significant attenuation. The superior electrochemical properties are attributed to their special nanotube structure with a high specific surface area, which could shorten the ion/electron transport pathway, and increase the number of active sites and the contact area between the electrolyte and active electrodes. Meanwhile, the kinetic analysis of the electrochemical behaviors of SNTO hollow nanotube electrodes was carried out by performing calculations using cyclic voltammograms recorded at different scan rates, and the results showed that the obtained reversible capacity is mainly due to the capacitive contribution. This work expands the types of anode materials for LIBs, which will further promote the development of LIBs. [ABSTRACT FROM AUTHOR]

MoS3 is a promising anode material due to its high theoretical capacity (838 mAh g−1), high conductivity, low cost, and environmental friendliness. However, the big volume changes upon cycling can induce particle pulverization, leading to a poor cycling performance, especially at high rates. Herein, nanocomposites of amorphous ultrasmall MoS3 nanoparticles and loaded graphene oxide (GO/MoS3) have been prepared via a facile acid precipitation method. Three nanocomposites were obtained by changing the amounts of GO. They were employed as anode materials for both lithium‐ and sodium‐ion batteries. Using GO as the buffer layer, the volume changes can be effectively suppressed. The material exhibits better lithium‐ and sodium‐storage performances than pure MoS3. An optimized nanocomposite containing 30 mg of GO shows the highest specific capacity of 685 mAh g−1 after 1000 cycles, even at 2 A g−1. Different from lithium‐ion batteries, the nanocomposite containing 50 mg of GO demonstrates a superior cycling stability in sodium‐ion batteries in comparison with the other nanocomposites. It delivers a high reversible specific capacity of 272 mAh g−1 after 700 cycles at 1 A g−1. The excellent electrochemical performances of these nanocomposites could be attributed to the synergistic effect of GO and MoS3. [ABSTRACT FROM AUTHOR]

The nickel metal nanoparticles and 3D nitrogen-doped carbon matrix are adopted to embellish nickel oxide via a simplified hard template method. This strategy will shine the route to prepare and ameliorate the electrochemical performance of NiO-based electrodes and other-type electrodes for energy storage. [Display omitted] Tailoring the omnidirectional conductivity networks in nickel oxide-based electrodes is important for ensuring their long lifespan, stability, high capacity, and high-rate capability. In this study, nickel metal nanoparticles and a three-dimensional nitrogen-doped carbon matrix were used to embellish the nickel oxide composite NiO–Ni/N–C via simplified hard templating. When a porous nitrogen-doped carbon matrix is present, a rapid pathway would be established for charging and discharging the electrons and lithium ions in a lithium-ion battery, thereby alleviating the volumetric expansion of the NiO nanoparticles during the operation of the battery. Moreover, the Ni0 ions added to serve as active sites to improve the capacity of the NiO-based electrodes and strengthen their conductivities. The multielement-effects of the optimal NiO–Ni/N–C electrode leads it to exhibit a capacity of 1310.8 mAh g-1 at 0.1 A g-1 for 120 loops and a rate capability of 441.5 mAh g-1 at 20.0 A g-1. Kinetic analysis of the prepared electrodes proved their ultrafast ionic and electronic conductivities. This strategy of hard templating reduces the number of routes required for preparing different types of electrodes, including NiO-based electrodes, and improves their electrochemical performance to enable their use in energy storage applications. [ABSTRACT FROM AUTHOR]

Spherical-graphite/Fe 2 O 3 composites have been synthesized through a facile and cost-effective strategy which contains initial co-precipitation reaction along with subsequent calcination process. The core-shell structure of composites is formed by coating some Fe 2 O 3 nanorods on the surface of spherical-graphite. This work verifies the optimal coating amount of Fe 2 O 3 , which is most beneficial for improvement of lithium storage performance. Indeed, all the composites deliver excellent rate capability and cycling stability in half-cell. The optimal spherical-graphite/Fe 2 O 3 composite with 8.7 wt% of Fe 2 O 3 exhibits a high reversible capacity of 540 mAh g−1 at 0.5 A g−1 and 376 mAh g−1 at 2 A g−1 after 200 and 1000 cycles, respectively. The electrochemical performance of full-cell with optimal composite as anode and LiFePO 4 as cathode has been investigated, which can retain 288 mAh g−1 at 0.1 A g−1 after 30 cycles. The outstanding lithium storage performance is lied in the synergistic effect of spherical-graphite and Fe 2 O 3 nanorods. The outer Fe 2 O 3 nanorods can significantly improve the lithium storage capacity, meanwhile the high-conductive spherical-graphite can suppress the volume changes of Fe 2 O 3. The above results demonstrate that the low-cost and simple synthesis strategy to prepare spherical-graphite/Fe 2 O 3 composites has sufficient potential to replace graphite for high performance lithium ion batteries. Image 1 • Spherical-graphite/Fe2O3 composites are prepared by a simple and low-cost process. • The composites show high lithium storage capacities and better rate performance. • The superior electrochemical performance at high mass loadings is obtained. • The electrochemical performance for full cell is investigated. • The synergistic effect of spherical-graphite and Fe2O3 nanorods. [ABSTRACT FROM AUTHOR]

In this work, a facile synthesis strategy was used to fabricate the carbon-coated new spinel Fe 1.5 V 1.5 O 4 nanorods. The initial obtained precursor was prepared by a facile solvothermal process. After it was treated by different methods, hierarchical Fe 1.5 V 1.5 O 4 @C nanorods consisted of Fe 1.5 V 1.5 O 4 primary nanoparticles with different particle sizes could be obtained. As anode materials for lithium ion batteries, the hierarchical Fe 1.5 V 1.5 O 4 @C nanorods composed of smaller primary particles show higher reversible capacity, better cycling performance and rate capability. Its reversible capacity can retain at 753 mAh g −1 and 709 mAh g −1 even cycled at 0.5 A g −1 and 2 A g −1 after 100 cycles and 1000 cycles, respectively. The excellent lithium storage performance of carbon-coated Fe 1.5 V 1.5 O 4 nanorods is dependent on the spinel crystal structure, unique hierarchical structure, and synergistic effect of active materials and carbon layer in the composites. The results of CV curves imply that the overall capacity upon cycling is determined by both of the surface-controlled capacitive contribution and diffusion-controlled Li + intercalation process. [ABSTRACT FROM AUTHOR]

• A novel orthorhombic bimetallic organic framework, [ZnCe(L 7)•2H 2 O] n was fabricated via a simple solvothermal reaction. • ZnSe/CeO 2 /RGO was successfully fabricated by a metal-organic-framework-engaged strategy. • ZnSe/CeO 2 /RGO shows excellent cycle stability and rate capability for Na+ and Li+ storage. • The redox reactions are dominated by pseudocapacitive behavior. [Display omitted] Metal-organic frameworks (MOFs) are used to derive inorganic material, which is an effective way to achieve high performance electrode materials for sodium-ion batteries (SIBs) and lithium ion batteries (LIBs). In this work, a novel orthorhombic bimetallic organic framework, [ZnCe(L 7)·2H 2 O]n (termed as ZnCeL, L = 5-aminoisophthalic acid) with 3D open framework was synthesized via a simple solvothermal reaction. Then ZnSe/CeO 2 /RGO was successfully fabricated via pyrolysis and selenization of ZnCeL and graphene oxide (RGO) composites. In the hybrid, ZnSe with high theoretical specific capacity and CeO 2 with electrocatalytic property are wrapped by conductive RGO. Herein, ZnSe/CeO 2 /RGO displays excellent sodium and lithium-storage performances. It reveals a sodium storage capacity of 113.2 mAh g−1 after 2000 cycles at 2.0 A g−1. Meanwhile, ZnSe/CeO 2 /RGO as an anode for LIBs delivers a reversible capacity of 675 mAh g−1 at 0.1 A g−1 after 200 cycles. The electrochemical kinetic analysis reveals that the redox reactions are dominated by pseudocapacitive behavior. The excellent performance reveals a bright prospect of the bimetallic organic frameworks derived inorganic material for energy storage. [ABSTRACT FROM AUTHOR]

Titanium carbide MXene as a new 2D anode material has been used for lithium ion batteries, due to its high electrical conductivity, low Li+ diffusion barriers and excellent chemical stability. Nevertheless, the low specific capacity of titanium carbide limits its application. Herein, we used facile ultrasonic and freeze drying methods to fabricate the ferroferric oxide (Fe 3 O 4) modified Ti 3 C 2 T x hybrids for lithium storage. In the hybrid, Fe 3 O 4 nanoclusters are homogeneously anchored on the surface of the single or few layered Ti 3 C 2 T x nanosheets by electrostatic interactions. Due to the synergistic effect of Fe 3 O 4 nanoclusters and Ti 3 C 2 T x nanosheets, all the prepared hybrids show superior lithium storage performance to the single titanium carbide and Fe 3 O 4 nanoclusters. The hybrid with weight ratio of Ti 3 C 2 T x nanosheets and Fe 3 O 4 (1:1) exhibits a high lithium storage capacity of 437.6 mA h g−1 after 100 cycles at 100 mA g−1. Even at a high current density of 2 A g−1, it still retains a stable capacity of 326.6 mA h g−1 after 1000 long cycles. The excellent lithium storage performance is proved to be the combination of battery and capacitance behaviors based on the kinetics analysis. This work demonstrates that Fe 3 O 4 nanoclusters decorated Ti 3 C 2 T x nanosheets hybrids are promising high performance anode materials for lithium ion batteries. Image 1 •. The s-Ti 3 C 2 T x /Fe 3 O 4 was prepared by ultrasonic and freeze drying methods. •. The s-Ti 3 C 2 T x /Fe 3 O 4 -1:1 exhibits excellent lithium storage performance. •. The reversible capacity can retain 326.6 mA h g−1 after 1000 cycles at 2 A g−1. •. The battery and capacitance behaviors contribute to the lithium storage capacity. [ABSTRACT FROM AUTHOR]