Ce-Doped PANI/Fe3O4 Nanocomposites: Electrode Materials for Supercapattery

In this study, we report on a combined approach to preparing an active electrode material for supercapattery application by making nanocomposites of Polyaniline/Cerium (PANI/Ce) with different weight percentages of magnetite (Fe3O4). Fourier-transform infrared spectroscopy (FTIR) and x-ray diffraction (XRD) analyses supported the interaction of PANI with Ce and the formation of the successful nanocomposite with magnetite nanoparticles. Scanning electron microscopy (SEM) and transmission electron microscopy (TEM) analyses showed the uniform and porous morphology of the composites. Cyclic voltammetry (CV) and galvanostatic charge–discharge (GCD) were used to test the supercapattery behavior of the nanocomposite electrodes in 1.0 M H2SO4. It was found that the supercapattery electrode of PANI/Ce+7 wt.% Fe3O4 exhibited a specific capacity of 171 mAhg−1 in the potential range of −0.2 to 1.0 V at the current density of 2.5 Ag−1. Moreover, PANI/Ce+7 wt.% Fe3O4 revealed a power density of 376.6 Wkg−1 along with a maximum energy density of 25.4 Whkg−1 at 2.5 Ag−1. Further, the cyclic stability of PANI/Ce+7 wt.% Fe3O4 was found to be 96.0% after 5,000 cycles. The obtained results suggested that the PANI/Ce+Fe3O4 nanocomposite could be a promising electrode material candidate for high-performance supercapattery applications.

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Facile Synthesis of Tremella-Like Li3V2(PO4)3/C Composite Cathode Materials Based on Oroxylum for Use in Lithium-Ion Batteries

Journal of Nanoscience and Nanotechnology ◽

10.1166/jnn.2020.17361 ◽

2020 ◽

Vol 20 (3) ◽

pp. 1962-1967

Author(s):

Zhen Liu ◽

Wei Zhou ◽

Guilin Zeng ◽

Yuling Zhang ◽

Zebin Wu ◽

...

Keyword(s):

Electron Microscopy ◽

Cathode Materials ◽

Specific Capacity ◽

Lithium Ion ◽

Composite Cathode ◽

Potential Range ◽

X Ray Diffraction ◽

Immersion Method ◽

X Ray ◽

Transmission Electron

Oroxylum as a traditional Chinese medicine, was used as a green and novel bio-template to synthesize tremella-like Li3V2(PO4)3/C composite (LVPC) cathode materials by adopting a facile immersion method. The microstructures were analyzed by X-ray diffraction analysis, scanning electron microscopy, and transmission electron microscopy. The electrochemical properties were investigated by galvanostatic charge–discharge experiments. The LVPC revealed specific capacity of 95 mAh·g-1 at 1 C rate within potential range of 3.0–4.3 V. After 100 cycles at 0.2 C, the retention of discharge capacity was 96%. The modified electrochemical performance is mainly resulted from the distinct tremella-like structure.

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Electrodeposition and Characterization of Mesoporous Nanostructured Cobalt Films using Brij78 Templated

Journal of New Materials for Electrochemical Systems ◽

10.14447/jnmes.v18i3.364 ◽

2015 ◽

Vol 18 (3) ◽

pp. 165-168 ◽

Cited By ~ 1

Author(s):

M. A. Ghanem ◽

I. S. El-Hallag

Keyword(s):

Electron Microscopy ◽

High Performance ◽

Electrode Materials ◽

X Ray Diffraction ◽

Uniform Size ◽

Cobalt Films ◽

Transmission Electron ◽

Ordered Mesoporous ◽

Mesoporous Thin Films

In this manuscript the preparation of highly ordered mesoporous cobalt films containing close packed arrays of spherical holes of uniform size was demonstrated by electrochemical deposition using the hexagonal liquid crystal template (H1-e Co). The template used was Brij®78 surfactant. Transmission electron microscopy (TEM), scanning electron microscopy (SEM), voltammetric methods, and low angle X-ray diffraction (XRD) were used to characterize the electrodeposited mesopores films. Cyclic voltammetry (CV) technique are used to show the mesoporous thin films are promising to be used as electrode materials of high - performance super capacitors.

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Nitrogen-Enriched Reduced Graphene Oxide for High Performance Supercapacitor Electrode

Journal of Nanoscience and Nanotechnology ◽

10.1166/jnn.2020.18496 ◽

2020 ◽

Vol 20 (8) ◽

pp. 4854-4859 ◽

Cited By ~ 2

Author(s):

Lei Chen ◽

Xu Chen ◽

Yaqiong Wen ◽

Bixia Wang ◽

Yangchen Wu ◽

...

Keyword(s):

Electron Microscopy ◽

Graphene Oxide ◽

Specific Capacitance ◽

Reduced Graphene Oxide ◽

Electrode Material ◽

High Performance ◽

Electrode Materials ◽

Electrochemical Impedance ◽

Oxide Electrode ◽

Reduced Graphene

Nitrogen-enriched reduced graphene oxide electrode material can be successfully prepared through a simple hydrothermal method. The morphology and microstructure of ready to use electrode material is measured by field emission scanning electron microscopy (FESEM), high-resolution transmission electron microscopy (HRTEM) and X-ray diffraction (XRD). Physical characterizations revealed that nitrogen-enriched reduced graphene oxide electrode material possessed high specific surface area of 429.6 m2 · g−1, resulting in high utilization of electrode materials with electrolyte. Electrochemical performance of nitrogen-enriched reduced graphene oxide electrode was also investigated by cyclic voltammetry (CV), galvanostatic charge/discharge measurements and electrochemical impedance spectroscopy (EIS) in aqueous in 6 M KOH with a three-electrode system, which displayed a high specific capacitance about 223.5 F · g−1 at 1 mV · s−1. More importantly, nitrogenenriched reduced graphene oxide electrode exhibited outstanding stability with 100% coulombic efficiency and with no specific capacitance loss under 2 A · g−1 after 10000 cycles. The supercapacitive behaviors indicated that nitrogen-enriched reduced graphene oxide can be a used as a promising electrode for high-performance super-capacitors.

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A Cryogenic Milling Method to Fabricate Nanostructured Anodes

10.26434/chemrxiv.13128026 ◽

2020 ◽

Author(s):

Qizhang Yan ◽

Shu-Ting Ko ◽

Yumin Zhao ◽

Grace Whang ◽

Andrew Dawson ◽

...

Keyword(s):

Electron Microscopy ◽

High Performance ◽

Electrode Materials ◽

Coulombic Efficiency ◽

Graphite Powder ◽

Cryogenic Milling ◽

Transmission Electron ◽

Scanning Transmission ◽

Battery Electrode ◽

Milling Method

Cryogenic milling was demonstrated as a new and facile method to fabricate nanostructured battery electrode materials. SnSb anode material with 1.2 wt% graphite was selected as a model system to demonstrate the feasibility and benefits of this method. Ball milling at a cryogenic temperature can suppress cold welding, exfoliate bulk graphite powder into nanoplatelets, and evenly disperse them between the grains. Aberration-corrected scanning transmission electron microscopy and post-cycling scanning electron microscopy showed refined grain sizes and well-dispersed carbon nanoplatelets, which can stabilize the nanostructure and alleviate volume expansion and cracking upon cycling. The cryomilled SnSb-C composite anode showed a reversible volumetric capacity of 1842 Ah/L, average coulombic efficiency of 99.6 ± 0.3%, and capacity retention of 90% over 100 cycles. The cryomilled sample showed improved electrochemical performance compared to the conventional ball milled specimen. This new method of cryogenic milling can produce various other high-performance nanostructured electrode materials.

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A Cryogenic Milling Method to Fabricate Nanostructured Anodes

10.26434/chemrxiv.13128026.v1 ◽

2020 ◽

Author(s):

Qizhang Yan ◽

Shu-Ting Ko ◽

Yumin Zhao ◽

Grace Whang ◽

Andrew Dawson ◽

...

Keyword(s):

Electron Microscopy ◽

High Performance ◽

Electrode Materials ◽

Coulombic Efficiency ◽

Graphite Powder ◽

Cryogenic Milling ◽

Transmission Electron ◽

Scanning Transmission ◽

Battery Electrode ◽

Milling Method

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Synthesis of MoO3/V2O5/C Composite as Novel Anode for Li-Ion Battery Application

Journal of Nanoscience and Nanotechnology ◽

10.1166/jnn.2020.17441 ◽

2020 ◽

Vol 20 (5) ◽

pp. 2911-2916

Author(s):

Zhen Zhang ◽

Xiao Chen ◽

Guangxue Zhang ◽

Chuanqi Feng

Keyword(s):

Electron Microscopy ◽

Photoelectron Spectroscopy ◽

Specific Capacity ◽

Lithium Ion ◽

Li Ion Battery ◽

X Ray Diffraction ◽

X Ray ◽

Transmission Electron ◽

Li Ion ◽

Battery Application

The MoO3/V2O5/C, MoO3/C and V2O5/C are synthesized by electrospinning combined with heat treatment. These samples are characterized by X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM), transmission electron microscopy (TEM), Raman spectroscopy and thermogravimetric analysis (TG) techniques. The results show that sample MoO3/V2O5/C is a composite composed from MoO3, V2O5 and carbon. It takes on morphology of the nanofibers with the diameter of 200~500 nm. The TG analysis result showed that the carbon content in the composite is about 40.63%. Electrochemical properties for these samples are studied. When current density is 0.2 A g−1, the MoO3/V2O5/C could retain the specific capacity of 737.6 mAh g−1 after 200 cycles and its coulomb efficiency is 92.99%, which proves that MoO3/V2O5/C has better electrochemical performance than that of MoO3/C and V2O5/C. The EIS and linear Warburg coefficient analysis results show that the MoO3/V2O5/C has larger Li+ diffusion coefficient and superior conductivity than those of MoO3/C or V2O5/C. So MoO3/V2O5/C is a promising anode material for lithium ion battery application.

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Cost-Effective Synthesis of Efficient CoWO4/Ni Nanocomposite Electrode Material for Supercapacitor Applications

Nanomaterials ◽

10.3390/nano10112195 ◽

2020 ◽

Vol 10 (11) ◽

pp. 2195

Author(s):

Kannadasan Thiagarajan ◽

Dhandapani Balaji ◽

Jagannathan Madhavan ◽

Jayaraman Theerthagiri ◽

Seung Jun Lee ◽

...

Keyword(s):

Electron Microscopy ◽

Electrode Material ◽

Composite Electrode ◽

Electrode Materials ◽

Supporting Electrolyte ◽

Cost Effective ◽

X Ray ◽

Transmission Electron ◽

Effective Synthesis ◽

Supercapacitor Applications

In the present study, the synthesis of CoWO4 (CWO)–Ni nanocomposites was conducted using a wet chemical method. The crystalline phases and morphologies of the Ni nanoparticles, CWO, and CWO–Ni composites were analyzed using X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), and energy-dispersive X-ray spectroscopy (EDAX). The electrochemical properties of CWO and CWO–Ni composite electrode materials were assessed by cyclic voltammetry (CV), and galvanostatic charge–discharge (GCD) tests using KOH as a supporting electrolyte. Among the CWO–Ni composites containing different amounts of Ni1, Ni2, and Ni3, CWO–Ni3 exhibited the highest specific capacitance of 271 F g−1 at 1 A g−1, which was greater than that of bare CWO (128 F g−1). Moreover, the CWO–Ni3 composite electrode material displayed excellent reversible cyclic stability and maintained 86.4% of its initial capacitance after 1500 discharge cycles. The results obtained herein demonstrate that the prepared CWO–Ni3 nanocomposite is a promising electrode candidate for supercapacitor applications.

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The preparation and electrochemical performance of Mo6S8 as cathode materials for magnesium ion batteries

International Journal of Modern Physics B ◽

10.1142/s0217979220400123 ◽

2019 ◽

Vol 34 (01n03) ◽

pp. 2040012

Author(s):

Zekun Wang ◽

Jianfeng Huang ◽

Jiayin Li

Keyword(s):

Electron Microscopy ◽

Electrochemical Performance ◽

Specific Capacity ◽

Reversible Capacity ◽

X Ray Diffraction ◽

Chevrel Phase ◽

Transmission Electron ◽

Magnesium Batteries ◽

Magnesium Ion Batteries ◽

Rechargeable Magnesium Batteries

In this work, we reported a Chevrel phase [Formula: see text], which was synthesized by a molten salt approach, and its electrochemical performance as a cathode material for rechargeable magnesium batteries. The phase composition and micromorphology of the product were measured and analyzed by X-ray diffraction, scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The Chevrel phase sulfide delivered an excellent specific capacity of 91 mAh g[Formula: see text] at a current density of 0.2 C after 70 cycles. Its excellent reversible capacity, rate performance and cycle stability demonstrate the feasibility of the Chevrel phase [Formula: see text] materials for future rechargeable magnesium batteries.

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Analysis of Composition and Valence States in Positive Electrode Materials (Fe-Substituted Li2MnO3) for Lithium Ion Batteries by Analytical Transmission Electron Microscopy

MRS Proceedings ◽

10.1557/proc-0972-aa06-08 ◽

2006 ◽

Vol 972 ◽

Author(s):

Jun Kikkawa ◽

Tomoki Akita ◽

Mitsuharu Tabuchi ◽

Masahiro Shikano ◽

Kuniaki Tatsumi ◽

...

Keyword(s):

Electron Microscopy ◽

Transmission Electron Microscopy ◽

Electrode Materials ◽

Specific Capacity ◽

Positive Electrode ◽

Analytical Transmission Electron Microscopy ◽

Local Composition ◽

Valence States ◽

Transmission Electron ◽

Fe And Mn

AbstractAnalytical transmission electron microscopy (ATEM) was applied to investigate local variation of composition of transition metals in each particle of Fe-substituted Li2MnO3, which reveals high specific capacity and high voltage as a positive electrode. Crystal lattice images of primary particles were observed by means of high-resolution TEM (HRTEM), where local composition of Fe and Mn was determined by electron energy-loss spectroscopy (EELS). It was found that there exist both manganese (Mn)-rich and iron (Fe)-rich regions in a primary particle, where concentration of Fe and Mn fluctuates irregularly in nanometer scale. The relationship between composition and crystal structure in each local region is discussed.

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Partially Graphitized Iron-Carbon Hybrid Composite as Electrochemical Supercapacitor Material

10.26434/chemrxiv.11369673 ◽

2020 ◽

Author(s):

Sai Rashmi M. ◽

Ashish Singh ◽

Chandra sekhar Rout ◽

Akshaya Samal ◽

Manav Saxena

Keyword(s):

Iron Oxide ◽

Current Density ◽

Electrode Material ◽

High Performance ◽

Electrode Materials ◽

Carbon Composite ◽

X Ray ◽

Transmission Electron ◽

Excellent Property ◽

A Current

The conversion of biomass into valuable carbon composites as an efficient non-precious energy storage electrode material have elicited extensive research interest. As synthesized partially graphitized iron oxide-carbon composite material (Fe3O4/Fe3C@C) shows an excellent property as an electrode material for supercapacitor. X-ray diffraction, High resolution transmission electron microscopy, X-ray photo-electron spectroscopy and Brunauer-Emmett-Teller analysis is used to study the structural, compositional and surface areal properties. The electrode material shows a specific surface area of 827.4 m2/g. Due to the synergistic effect of graphitic layers with iron oxide/carbide, Fe3O4/Fe3C@C hybrid electrode materials display high-performance for supercapacitor with excellent capacity of 878 F/g at a current density of 5A/g (3-electrode) and 211.6 F/g at a current density of 0.4A/g (2-electrode) in 6M KOH electrolyte with good cyclic stability.

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