Facile synthesized Cu-SnO2 anode materials with three-dimensional metal cluster conducting architecture for high performance lithium-ion batteries

A novel Cu-SnO₂ anode material derived from Cu₆Sn₅ alloy, retaining high conductivity of Cu and high theoretical capacity of SnO₂ with a facile synthesizing process by oxidation and reduction method. The novel Cu structure penetrates in the composite particles inducing high conductivity and spaceconfined SnO₂, which restrict the pulverization of SnO₂ during lithiation/delithiation process.     

Bismuth oxide nanoflake@carbon film: A free-standing battery-type electrode for aqueous sodium ion hybrid supercapacitors

An efficient strategy is developed to fabricate binder-free Bi₂O₃@C nanoflake film anode, which is utilized to assemble a high-performance aqueous sodium ion hybrid supercapacitor.     

Effect of bication (Cu-Cr) substitution on the structure and electrochemical performance of LiMn2O4 spinel cathodes at low and high current rates

This report describes the detailed structural and electrochemical characterization of a series of low content (0.01 to 0.05) Cu-Cr bi-metal doped LiMn₂O₄ cathode material synthesized by sol–gel method. The structural and morphological features were described using XRD, SEM, TEM, EDAX and FTIR techniques. The electron transfer and its feasibility were discussed through cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS) measurements. The charge–discharge studies were performed to evaluate the capacity fading and rate capability. It was found that the electrochemical performance is very much dependent on the amount of Cu-Cr bi-metal doping and interestingly decreased the capacity fading with high cycleability. The sample with the least amount of dopants (i.e., LiCu_0.01Cr_0.01Mn_1.98O₄) demonstrated much improved capacity, cycleability and high rate capability. The LiCu_0.01Cr_0.01Mn_1.98O₄ cathode exhibited a discharge capacity of 112 mA h g^?1 at very first cycle and retained 93 mA h g^?1 after 100 cycles at a C rate of 0.3. Further, the same material at very high current density (5 C) retained 83% of the initial discharge capacity. The Cu-Cr doping stabilized the spinel structure by suppressing the Jahn-Teller distortion effect and Mn dissolution and the resultant material showed the workability of the cathodes for devices which work at substantially high C-rate of 5C.     

Protection of Li metal anode by surface-coating of PVDF thin film to enhance the cycling performance of Li batteries

The PVDF thin film on the surface of the lithium metal can highly suppress the lithium dendrites.     

Ultrafine molybdenum carbide nanoparticles supported on nitrogen doped carbon nanosheets for hydrogen evolution reaction

Nitrogen doped carbon nanosheets supported molybdenum carbides nanoparticles (Mo_xC/NCS) have been synthesized by tuning the mass ratio of melamine and ammonia molybdate. The Mo₂C/NCS-10 exhibits superior electrocatalytic performance and stability for HER, which was attributed to N-doped carbon nanosheets, small particle size, mesoporous structure, and large electrochemical active surface area.     

Flexible asymmetric supercapacitor based on MnO2 honeycomb structure

By controlling the electroplating time of solution containing Mn(Ac)₂, the MnO₂ nanosheets were self-assembled to the honeycomb structure and showed an excellent electrochemical performance in 1 mol/L Na₂SO₄ electrolyte. Via pairing with activated carbon as negative electrode, the capacitor could deliver a maximum energy density of 43.84 Wh/kg and a maximum power density of 6.62 kW/kg.     

Mesoporous carbon material as cathode for high performance lithium-ion capacitor

The mesoporous carbon material with large pore volume and high surface area by a simple situ MgO template method is synthesized, which is utilized as cathode to assemble a high performance lithium ion capacitor.     

Structural and electrochemical investigation of Li2MgSnO4 anode for lithium batteries

Hexagonal Li₂MgSnO₄ compound was synthesized at 800 °C using Urea Assisted Combustion (UAC) method and the same has been exploited as an anode material for lithium battery applications. Structural investigations through X-ray diffraction, Fourier Transform Infra Red spectroscopy and ⁷Li NMR (Nuclear Magnetic Resonance spectroscopy) studies demonstrated the existence of hexagonal crystallite structure with a = 6.10 and c = 9.75. An average crystallite size of ∼400 nm has been calculated from PXRD pattern, which was further evidenced by SEM images. An initial discharge capacity of ∼794 mA h/g has been delivered by Li₂MgSnO₄ anode with an excellent capacity retention (85%) and an enhanced coulombic efficiency (97–99%). Further, the Li₂MgSnO₄ anode material has exhibited a steady state reversible capacity of ∼590 mA h/g even after 30 cycles, thus qualifying the same for use in futuristic lithium battery applications.     

High capacity and excellent cyclability of vanadium (IV) oxide in lithium battery applications

A VO₂ · 0.43H₂O powder with a flaky particle morphology was synthesized via a hydrothermal reduction method. It was characterized by scanning electron microscopy, electron energy loss spectroscopy, and thermogravimetric analysis. As an electrode material for rechargeable lithium batteries, it was used both as a cathode versus lithium anode and as an anode versus LiCoO₂, LiFePO₄ or LiNi_0.5Mn_1.5O₄ cathode. The VO₂ · 0.43H₂O electrode exhibits an extraordinary superiority with high capacity (160 mAh g^?1), high energy efficiency (95%), excellent cyclability (142.5 mAh g^?1 after 500 cycles) and rate capability (100 mAh g^?1 at 10 C-rate).     

Magnetite/carbon core-shell nanorods as anode materials for lithium-ion batteries

Carbon coated magnetite (Fe₃O₄) core-shell nanorods were synthesized by a hydrothermal method using Fe₂O₃ nanorods as the precursor. Transmission electron spectroscopy (TEM) and high resolution TEM (HRTEM) analysis indicated that a carbon layer was coated on the surfaces of the individual Fe₃O₄ nanorods. The electrochemical properties of Fe₃O₄/carbon nanorods as anodes in lithium-ion cells were evaluated by cyclic voltammetry, ac impedance spectroscopy, and galvanostatic charge/discharge techniques. The as-prepared Fe₃O₄/C core-shell nanorods show an initial lithium storage capacity of 1120 mAh/g and a reversible capacity of 394 mAh/g after 100 cycles, demonstrating better performance than that of the commercial graphite anode material.     

Polyimide-derived carbon nanofiber membranes as anodes for high-performance flexible lithium ion batteries

Heteroatoms-doped carbon nanofiber membranes with flexible features were prepared by electrospinning with heterocyclic polyimide (PI) structures containing biphenyl and pyrimidine rings. The products with optimized treatment could achieve 695 mAh/g at 0.1 A/g and retain 245 mAh/g at 1.5 A/g after 300 cycles when used as anode for Li-ion batteries.     

Synthesis of MXene-supported layered MoS2 with enhanced electrochemical performance for Mg batteries

In this paper, the petal-like MoS₂/MXene composite has been successfully synthesized by one-step hydrothermal method. With the combination of few-layer MoS₂ nanosheets and the high conductive MXene substrate, the composite exhibits enhanced capacities and rate performance as cathode material of Mg batteries.     

Tremella-like molybdenum dioxide consisting of nanosheets as an anode material for lithium ion battery

Tremella-like structured MoO₂ consisting of nanosheets was obtained via a Fe₂O₃-assisted hydrothermal reduction of MoO₃ in ethylenediamine aqueous solution. The as-prepared product was characterized and tested with scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray powder diffraction (XRD), X-ray photoelectron spectroscopy (XPS), cyclic voltammetry (CV) and capacity measurement as anode material for lithium ion batteries. This structured MoO₂ shows very high reversible capacity (>600 mA h g⁻¹), good rate capability and cycling performance, presenting potential application as anode material for lithium ion batteries with high rate capability and high capacity.     

Chrysanthemum-like Co3O4 architectures: Hydrothermal synthesis and lithium storage performances

Three-dimensional chrysanthemum-like Co₃O₄ was prepared via a facile hydrothermal route without any template, and a subsequent calcination process. With a controlled concentration of the homogeneous precipitation agent, urea, a chrysanthemum-like precursor was hydrothermally obtained at 120 °C for 20 h, and the morphology was kept for Co₃O₄ after a subsequent calcination at 300 °C for 2 h. Co₃O₄ chrysanthemum-like architectures are assemblies of nanorods radiating from a common centre, and the nanorods consisted of interconnected nanoparticles with the size of about 30 nm. When tested as an anode material of Li-ion batteries, chrysanthemum-like Co₃O₄ presented a discharge capacity of ∼450 mA h/g after 50 discharge/charge cycles.     

Li2ZnTi3O8 nanorods: A new anode material for lithium-ion battery

Spinel Li₂ZnTi₃O₈ nanorods were first synthesized using titanate nanowires as a precursor. The synthesized nanorods are highly crystalline and used as an anode material in a rechargeable Li-ion battery. A large capacity of 220 mA h g^? 1 was kept after 30 cycles at a current density of 0.1 A g^? 1, which is close to the theoretic capacity. The electrochemical measurements indicate that the anode material made of spinel Li₂ZnTi₃O₈ nanorods displayed a highly reversible capacity and excellent cycling stability.     

Laser processed micro-supercapacitors based on carbon nanotubes/manganese dioxide nanosheets composite with excellent electrochemical performance and aesthetic property

A laser processed micro-supercapacitor (LPMS) based on carbon nanotubes/manganese dioxide composite is fabricated through slurry dispensing and laser scribing techniques. This device presents superior electrochemical performance and aesthetic property.     

A novel single phase cathode material for a proton-conducting SOFC

A novel single phase BaCe_0.5Bi_0.5O_3 ? δ (BCB) was employed as a cathode material for a proton-conducting solid oxide fuel cell (SOFC). The single cell, consisting of a BaZr_0.1Ce_0.7Y_0.2O_3 ? δ (BZCY7)-NiO anode substrate, a BZCY7 anode functional layer, a BZCY7 electrolyte membrane and a BCB cathode layer, was assembled and tested from 600 to 700 °C with humidified hydrogen (～3% H₂O) as the fuel and the static air as the oxidant. An open-circuit potential of 0.96 V and a maximum power density of 321 mW cm^?2 were obtained for the single cell. A relatively low interfacial polarization resistance of 0.28Ω cm² at 700 °C indicated that the BCB was a promising cathode material for proton-conducting SOFCs.     

Si–AB5 composites as anode materials for lithium ion batteries

The Si–AB₅ (MmNi_3.6Co_0.7Al_0.3Mn_0.4 alloy) composites with a high tap density as anode materials for lithium-ion batteries were synthesized by ball-milling. Si nanoparticles are distributed homogeneously on the surface of the AB₅ matrix. The electrochemical performance of the Si–AB₅ composites as a function of Si content was investigated. It is demonstrated that the Si–AB₅ composite delivers a larger reversible capacity and better cycle ability because the inactive AB₅ alloy can accommodate the large volume changes of Si nanoparticles distributed on the surface of the Si–AB₅ composite during cycling. In particular, the Si–AB₅ composite containing 20 wt% Si with the high tap density of 2.8 g/cm³ obtained after ball-milling for 11 h exhibits an initial and maximum reversible (charge) capacity of 370 and 385 mAh/g. The high capacity retention can be achieved after 50 cycles in the potential range from 0.02 to 1.5 V.     

Partially reduced SnO2 nanoparticles anchored on carbon nanofibers for high performance sodium-ion batteries

One-dimensional (1-D) carbon nanofibers anchored with partially reduced SnO₂ nanoparticles (SnO₂/Sn@C) were successfully synthesized through a simple electrospinning method followed by carbon coating and thermal reduction processes. The partially reduced Sn frameworks, combined with the carbon fibers, provide a more favorable mechanism for sodiation/desodiation than SnO₂. As a result, SnO₂/Sn@C exhibits a high reversible capacity (536 mAh g^− 1 after 50 cycles) and an excellent rate capability (396 mAh g^− 1 even at 2 C rate) when evaluated as an anode material for sodium-ion batteries (SIBs).     

Non-metallic gold nanoclusters for oxygen activation and aerobic oxidation

In this review, oxygen activation and their aerobic oxidation over the Au nanoclusters are presented. The size-specificity, ligand engineering, and doping effects and the proposed reactions’ mechanism and the structure-activity relationships at the atomic level are also discussed.