scholarly journals Novel Bimetallic Tin-Manganese Oxides/Carbon Nanotube Nanocomposite and Their Charge Storage Properties

2014 ◽  
Vol 75 (1) ◽  
Author(s):  
Ir. Dr Ng Kok Chiang ◽  
Ms. Siew Shee Lim ◽  
Dr Chuang Peng
Keyword(s):  
High Performance ◽  
Manganese Oxides ◽  
Electrode Materials ◽  
Electronic Conductivity ◽  
Synergetic Effect ◽  
Charge Storage ◽  
X Ray Diffraction ◽  
Transmission Electron ◽  
Transport Of Ions ◽  
Storage Properties

The synthesis of CNTs/(Sn+Mn)Ox nanocomposites were first attempted through combining the hydro-oxidation of SnCl2 to SnO2 and the reduction of KMnO4 to MnO2 onto CNTs in this work. The reducing presence of SnCl2 accelerated the deposition of MnO2 from 7 days to a day. Subsequently, CNTs/(Sn+Mn)Ox nanocomposites were characterised by X-ray diffraction, scanning and transmission electron microscopy, cyclic voltammetry, and galvanostatic charge-discharge. These microstructure and electrochemical results indicated that this nanocomposite showed synergetic effect in term of specific capacitance, charge storage capacities and exceptional cycling stability. All these enhanced electrochemical properties were attributed to increased surface area, increased utilisation of co-deposited cassiterite-type SnO2 nanoparticulates and birnessite MnO2 monolayer. Additionally, their improved electronic conductivity facilitated better mass transport of ions during charging and discharging process. Based on the findings above, CNTs/(Sn+Mn)Ox nanocomposite will be served as promising and affordable positive electrode materials for high performance supercapacitors.

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

2021 ◽  
Vol 3 ◽  
Author(s):  
Subash Pandey ◽  
Shova Neupane ◽  
Dipak Kumar Gupta ◽  
Anju Kumari Das ◽  
Nabin Karki ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Electrode Material ◽  
High Performance ◽  
Electrode Materials ◽  
Specific Capacity ◽  
Maximum Energy ◽  
Potential Range ◽  
X Ray Diffraction ◽  
Active Electrode ◽  
Transmission Electron

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.

scholarly journals Electrodeposition and Characterization of Mesoporous Nanostructured Cobalt Films using Brij78 Templated

2015 ◽  
Vol 18 (3) ◽  
pp. 165-168 ◽  
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.

scholarly journals Hydrothermal Synthesis of Iodine-Doped Nanoplates with Enhanced Visible and Ultraviolet-Induced Photocatalytic Activities

2012 ◽  
Vol 2012 ◽  
pp. 1-12 ◽  
Author(s):  
Jiang Zhang ◽  
Zheng-Hong Huang ◽  
Yong Xu ◽  
Feiyu Kang
Keyword(s):  
Photocatalytic Activity ◽  
Photoelectron Spectroscopy ◽  
Oxygen Vacancies ◽  
Diffuse Reflectance Spectroscopy ◽  
Synergetic Effect ◽  
X Ray Diffraction ◽  
X Ray ◽  
Selected Area Electron Diffraction ◽  
Transmission Electron ◽  
Photocatalytic Activities

The iodine-doped Bi2WO6(I-BWO) photocatalyst was prepared via a hydrothermal method using potassium iodide as the source of iodine. The samples were characterized by X-ray diffraction (XRD), scanning electron microscope (SEM), transmission electron microscopy (TEM) and selected area electron diffraction (SAED), X-ray photoelectron spectroscopy (XPS), UV-vis diffuse reflectance spectroscopy (DRS), and photoluminescence (PL) spectroscopy. The photocatalytic activity of I-BWO for the degradation of rhodamine B (RhB) was higher than that of pure BWO and I2-BWO regardless of visible light (>420 nm) or ultraviolet light (<400 nm) irradiation. The results of DRS analysis showed that the I-BWO and I2-BWO catalysts had narrower band gaps. XPS analysis proved that the multivalent iodine species including I0and were coadsorbed on the defect surface of Bi2WO6in I-BWO. The enhanced PL intensity revealed that a large number of defects of oxygen vacancies were formed by the doping of iodine. The enhanced photocatalytic activity of I-BWO for degradation of RhB was caused by the synergetic effect of a small crystalline size, a narrow band gap, and plenty of oxygen vacancies.

scholarly journals Nitrogen, Phosphorus and Sulfur Co-Doped Pyrolyzed Bacterial Cellulose Nanofibers for Supercapacitors

Nanomaterials ◽  
2020 ◽  
Vol 10 (10) ◽  
pp. 1912
Author(s):  
Zheng Li ◽  
Yaogang Wang ◽  
Wen Xia ◽  
Jixian Gong ◽  
Shiru Jia ◽  
...  
Keyword(s):  
Bacterial Cellulose ◽  
High Performance ◽  
Electrode Materials ◽  
Cellulose Nanofibers ◽  
Electrochemical Performances ◽  
X Ray Diffraction ◽  
X Ray ◽  
Diffraction Patterns ◽  
Nitrogen Phosphorus ◽  
Co Doped

Heteroatom doping is an effective way to raise the electrochemical properties of carbon materials. In this paper, a novel electrode material including nitrogen, phosphorus, and sulfur co-doped pyrolyzed bacterial cellulose (N/P/S-PBC) nanofibers was produced. The morphologies, structure characteristics and electrochemical performances of the materials were investigated by Scanning electron microscopy, Fourier transform infrared spectra, X-ray diffraction patterns, X-ray photoelectronic spectroscopy, N2 sorption analysis and electrochemical measurements. When 3.9 atom% of nitrogen, 1.22 atom% of phosphorus and 0.6 atom% of sulfur co-doped into PBC, the specific capacitance of N/P/S-PBC at 1.0 A/g was 255 F/g and the N/P/S-PBC supercapacitors’ energy density at 1 A/g was 8.48 Wh/kg with a power density of 489.45 W/kg, which were better than those of the N/P-PBC and N/S-PBC supercapacitors. This material may be a very good candidate as the promising electrode materials for high-performance supercapacitors.

scholarly journals Electrode Materials for High-Performance Sodium-Ion Batteries

Materials ◽  
2019 ◽  
Vol 12 (12) ◽  
pp. 1952 ◽  
Author(s):  
Santanu Mukherjee ◽  
Shakir Bin Mujib ◽  
Davi Soares ◽  
Gurpreet Singh
Keyword(s):  
High Performance ◽  
Large Scale ◽  
Electrode Materials ◽  
State Of The Art ◽  
Electronic Conductivity ◽  
Lithium Ion ◽  
Cycle Life ◽  
Sodium Ion ◽  
Sodium Ion Batteries ◽  
Grid Storage

Sodium ion batteries (SIBs) are being billed as an economical and environmental alternative to lithium ion batteries (LIBs), especially for medium and large-scale stationery and grid storage. However, SIBs suffer from lower capacities, energy density and cycle life performance. Therefore, in order to be more efficient and feasible, novel high-performance electrodes for SIBs need to be developed and researched. This review aims to provide an exhaustive discussion about the state-of-the-art in novel high-performance anodes and cathodes being currently analyzed, and the variety of advantages they demonstrate in various critically important parameters, such as electronic conductivity, structural stability, cycle life, and reversibility.

Graphene-Wrapped FeOOH Nanorods with Enhanced Performance as Lithium-Ion Battery Anode

NANO ◽  
2020 ◽  
pp. 2150005
Author(s):  
Meng Sun ◽  
Zhipeng Cui ◽  
Huanqing Liu ◽  
Sijie Li ◽  
Qingye Zhang ◽  
...  
Keyword(s):  
High Performance ◽  
Electrode Materials ◽  
Electronic Conductivity ◽  
Rate Capability ◽  
Lithium Ion ◽  
Extraction Process ◽  
Hybrid Structure ◽  
Charge Transfer Resistance ◽  
Transfer Resistance ◽  
Distinctive Structure

FeOOH nanorods (NRs) wrapped by reduced graphene oxide (rGO) were fabricated using a facile solvothermal method. When used as anode materials for lithium-ion batteries (LIBs), the FeOOH NRs/rGO composites show a higher capacity (490[Formula: see text]mAh g[Formula: see text] after 100 cycles at a current density of 100[Formula: see text]mA g[Formula: see text] and better rate capability than pure FeOOH NRs. The enhanced electrochemical performance can be ascribed to the hybrid structure of FeOOH and rGO. On one hand, the introduction of rGO can improve electronic conductivity and reduce charge-transfer resistance for electrode materials. On the other hand, the distinctive structure (FeOOH NRs surrounded by flexible rGO) can effectively buffer large volume change during the Li[Formula: see text] insertion/extraction process. Our work provides a feasible strategy to obtain high-performance LIBs.

scholarly journals A Pd/MnO2 Electrocatalyst for Nitrogen Reduction to Ammonia under Ambient Conditions

Catalysts ◽  
2020 ◽  
Vol 10 (7) ◽  
pp. 802
Author(s):  
Chang Sun ◽  
Yingxin Mu ◽  
Yuxin Wang
Keyword(s):  
High Performance ◽  
High Efficiency ◽  
Pd Nanoparticles ◽  
Ambient Conditions ◽  
X Ray Diffraction ◽  
Hydrogen Electrode ◽  
Faradaic Efficiency ◽  
Transmission Electron ◽  
Alternative Approach ◽  
Supported Pd

Electrochemical ammonia synthesis, which is an alternative approach to the Haber–Bosch process, has attracted the attention of researchers because of its advantages including mild working conditions, environmental protection, and simple process. However, the biggest problem in this field is the lack of high-performance catalysts. Here, we report high-efficiency electroreduction of N2 to NH3 on γ-MnO2-supported Pd nanoparticles (Pd/γ-MnO2) under ambient conditions, which exhibits excellent catalytic activity with an NH3 yield rate of 19.72 μg·mg−1Pd h−1 and a Faradaic efficiency of 8.4% at −0.05 V vs. the reversible hydrogen electrode (RHE). X-ray diffraction (XRD) and transmission electron microscopy (TEM) characterization shows that Pd nanoparticles are homogeneously dispersed on the γ-MnO2. Pd/γ-MnO2 outperforms other catalysts including Pd/C and γ-MnO2 because of its synergistic catalytic effect between Pd and Mn.

Facile hydrothermal synthesis of ternary CeO2–SnO2/rGO nanocomposite for supercapacitor application

2020 ◽  
Vol 13 (02) ◽  
pp. 2051005 ◽  
Author(s):  
Godlaveeti Sreenivasa Kumar ◽  
Somala Adinarayana Reddy ◽  
Hussen Maseed ◽  
Nagireddy Ramamanohar Reddy
Keyword(s):  
Electron Microscope ◽  
Specific Capacitance ◽  
High Performance ◽  
High Specific Capacitance ◽  
Energy Storage And Conversion ◽  
X Ray Diffraction ◽  
X Ray ◽  
Supercapacitor Application ◽  
Transmission Electron ◽  
One Step

In this work, we present the synthesis of a ternary CeO2–SnO2/rGO nanocomposite by using a facile one-step hydrothermal method. The as-synthesized composite was structural, chemical, morphological, elemental information studied by using different characterization techniques X-ray diffraction (XRD), Fourier transform infrared (FTIR) spectroscopy and field emission scanning electron microscope (FESEM), energy dispersive X-ray spectroscopy (EDAX) and transmission electron microscope (TEM). The CeO2–SnO2/rGO exhibited an excellent specific capacitance of 156[Formula: see text]F[Formula: see text][Formula: see text] at 0.5[Formula: see text]A/g in the presence of 3 M KOH solution. The synergic effect of CeO2, SnO2 and graphene composite coated on Ni foam endowed a high specific capacitance than their individual compounds. This work suggests that the novel ternary composite is a promising candidate for the high performance electrochemical energy storage and conversion systems.

Controllable one-step synthesis of ZnO nanostructures using molybdophosphoric acid

2014 ◽  
Vol 68 (4) ◽  
Author(s):  
Hamed Rashidi ◽  
Ali Ahmadpour ◽  
Fatemeh Bamoharram ◽  
Seyed Zebarjad ◽  
Majid Heravi ◽  
...  
Keyword(s):  
Photocatalytic Degradation ◽  
High Performance ◽  
Hydrothermal Reaction ◽  
Hexagonal Phase ◽  
Zno Nanostructures ◽  
Molybdophosphoric Acid ◽  
X Ray Diffraction ◽  
Experimental Conditions ◽  
Transmission Electron ◽  
One Step

AbstractZnO nanostructures were synthesised in a hydrothermal reaction of zinc acetate in the presence of molybdophosphoric acid (H3[PMo12O40]) as well as its vanadium-substituted acid (H4[PMo11VO40]) at various times, temperatures, and concentrations. The ZnO nanostructures were characterised by X-ray diffraction, transmission electron microscopy, and Fourier transform infrared spectroscopy. The results demonstrated that the synthesised products are crystalline with a zincite hexagonal phase. Various ZnO nanostructures, such as nanoparticles, microrods, and nanosheets, were produced by changing the experimental conditions. The photocatalytic degradation of methyl orange was also investigated using the ZnO nanoparticles thus prepared. These particles exhibited high performance in the photocatalytic degradation of MO and almost 100 % decolourisation occurred within only 20 min.

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