A Porous Carbon Prepared by Using a Mordenite Mineral as Template and its Cyclic Voltammetry Study in H2SO4

2010 ◽  
Vol 143-144 ◽  
pp. 749-752
Author(s):  
Gui Yang Liu ◽  
Yan Nan Li ◽  
Jun Ming Guo ◽  
Bao Sen Wang
Keyword(s):  
Cyclic Voltammetry ◽  
Phase Composition ◽  
Rate Capability ◽  
Nitrogen Adsorption ◽  
X Ray Diffraction ◽  
X Ray ◽  
Scan Rate ◽  
Micro Morphology ◽  
Good Rate Capability ◽  
Templated Carbon

A natural mordenite mineral has been used as a template to prepare a templated carbon. X-ray diffraction (XRD), nitrogen adsorption, scanning electric microscope (SEM) and cyclic voltammetry (CV) are used to analyze the phase composition, pore structure, micro morphology and electrochemical performance. The specific surface area of the templated carbon is 724m2/g, and the mesoporosity is high to 63.8%. In H2SO4 medium, the carbon has large capacity and good rate capability. The capacity of the carbon decreases from 103 to 94F/g (the capacity remains more than 92%) when the scan rate increases from 10 to 200mV/s. The CV curve of the templated carbon exhibits rectangle-like shape, and the shape keeps well at high scan rate.

A Templated Carbon Prepared by Using a Clinoptilolite-Ca Mineral as Template and Furfuralcohol as Carbon Source: Pore Structure and Electrochemical Performance in H2SO4

2011 ◽  
Vol 66-68 ◽  
pp. 764-767
Author(s):  
Gui Yang Liu ◽  
Jun Ming Guo ◽  
Lili Zhang ◽  
Bao Sen Wang ◽  
Ying He
Keyword(s):  
Carbon Source ◽  
Electrochemical Performance ◽  
Pore Structure ◽  
Rate Capability ◽  
Nitrogen Adsorption ◽  
X Ray Diffraction ◽  
Scan Rate ◽  
Micro Morphology ◽  
Good Rate Capability ◽  
Templated Carbon

A templated carbon has been prepared by using a clinoptilolite-Ca mineral as template and furfuralcohol as carbon source. X-ray diffraction (XRD), nitrogen adsorption, scanning electric microscope (SEM) and cyclic voltammetry (CV) are used to analyze the phase composition, pore structure, micro morphology and electrochemical performance. The specific surface area of the templated carbon is 590m2/g and the mesoporosity is high to 63.4%. In H2SO4 medium, due to its rich mesopores, the carbon exhibits a large capacity and a good rate capability. The capacity of the carbon is 174F/g at a scan rate of 5mV/s. When the scan rate increases from 5 to 300mV/s, the capacity of the carbon decreases only from 174 to 144F/g, exhibiting a good rate capability.

Excellent Rate Capability in H2SO4 of a Porous Carbon Prepared by Template Method Using a Mazzite Mineral as Template

2011 ◽  
Vol 230-232 ◽  
pp. 1173-1176
Author(s):  
Gui Yang Liu ◽  
Yan Nan Li ◽  
Jun Ming Guo ◽  
Bao Sen Wang
Keyword(s):  
Cyclic Voltammetry ◽  
Phase Composition ◽  
Electrochemical Performance ◽  
Porous Carbon ◽  
Rate Capability ◽  
Template Method ◽  
X Ray Diffraction ◽  
X Ray ◽  
Structure Morphology ◽  
Scan Rate

A porous carbon was prepared by template method using a mazzite mineral as a template. X-ray diffraction (XRD), nitrogen adsoption, scanning electric microscope (SEM) and cyclic voltammetry (CV) were used to investigate the phase composition, pore structure, morphology and electrochemical performance of the carbon. The surface area of the carbon is 511m2/g. The pores of the carbon are mcropores and mesopores. In H2SO4 medium, the carbon exhibits a low capacity and a rectangle-like shaped CV curve at low scan rate. When the scan rate increases from 10 to 200mV/s, the capacity decreases only from 47 to 41F/g, and the rectangle-like shape keeps well. The carbon exhibits an excellent rate capability.

Electrochemical performance of M3(BTC)2·12H2O (M=Co, Ni, and Zn) for Supercapacitors

2011 ◽  
Vol 15 (2) ◽  
pp. 79-82
Author(s):  
Chenmin Liao ◽  
Jiachang Zhao ◽  
Bohejin Tang ◽  
Aomin Tang ◽  
Yanhong Sun ◽  
...  
Keyword(s):  
Cyclic Voltammetry ◽  
Electrochemical Impedance ◽  
Metal Organic Frameworks ◽  
X Ray Diffraction ◽  
X Ray ◽  
Scan Rate ◽  
Metal Organic ◽  
Acetate Hydrate ◽  
Xrd Patterns ◽  
Maximum Specific Capacitance

A series of Metal-Organic Frameworks (MOFs) based on 1,3,5-benzenetricarboxylic (BTC) acid and M(II) acetate hydrate (M=Co, Ni, and Zn) were successfully synthesized and named as M3(BTC)2·12H2O. These compounds were examined by X-ray diffraction (XRD) patterns. Electrochemical properties of the materials were characterized by cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS) in 6 M KOH aqueous solutions. The maximum specific capacitance of Ni3(BTC)2·12H2O is found to be 429 F g-1 at 5 mV s-1 and 154 F g-1 at 200 mV s-1 scan rate.

Particle Morphology and Electrochemical Performance of LiFePO4 Synthesized via Hydrothermal Process at 200°C

2011 ◽  
Vol 391-392 ◽  
pp. 926-930
Author(s):  
Lin Jing Zhang ◽  
Bo Rong Wu ◽  
Ning Li ◽  
Feng Wu
Keyword(s):  
Electrochemical Performance ◽  
Ph Value ◽  
Hydrothermal Process ◽  
Rate Capability ◽  
Particle Morphology ◽  
Solution Concentration ◽  
Particle Sizes ◽  
X Ray Diffraction ◽  
X Ray ◽  
Good Rate Capability

LiFePO4powders were synthesized from LiOH•H2O, FeSO4•7H2O, and H3PO4 via the hydrothermal process at 200。C . The particle sizes, morphology and electrochemical performance of the as-synthesized LiFePO4particles varied from the pH value, reaction time and solution concentration of the precursor. The as-prepared samples were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM) and galvaostdtic charge-discharge tests. The results indicated that the samples with carbon coating after reacting at pH value of 9 for 4h exhibited good rate capability, which had small particle size and plate-like morphology.

Effect of N2 Pressure on the Phase Composition and Morphology of Ti2AlN Prepared by Self-Propagating Combustion Method

2013 ◽  
Vol 710 ◽  
pp. 199-202
Author(s):  
Jia Jin Tian ◽  
Feng Rui Zhai ◽  
Li Li Zhang ◽  
Gui Yang Liu ◽  
Zhi Mei Ding
Keyword(s):  
Phase Composition ◽  
Raw Materials ◽  
Synthesis Method ◽  
Combustion Method ◽  
Xrd Analysis ◽  
Relative Content ◽  
X Ray Diffraction ◽  
X Ray ◽  
High Temperature Synthesis ◽  
Micro Morphology

Ti2AlN ceramic have been prepared by self-propagating high-temperature synthesis method using Ti, Al and TiAl mixture as raw materials under different N2 pressures. X-ray diffraction (XRD) and scanning electron microscope (SEM) have been used to determine the phase composition and micro morphology of the products. XRD analysis indicates that the main phase of the products is layered ternary compound Ti2AlN, but there are TiN and AlTi3 impurities in the products. With increasing N2 pressure, the relative content of TiN increases, whereas the relative content of AlTi3 decreases. SEM imagines exhibits that layered grains of the products become larger and tighter with increasing N2 pressures.

Preparation and Performance of Co3O4/Polyaniline Nano-Composite for Supercapacitor

2011 ◽  
Vol 239-242 ◽  
pp. 2042-2045 ◽  
Author(s):  
Shu Ping Yu ◽  
Xiao Cong Chang ◽  
Zhong Ming Wang ◽  
Ke Fei Han ◽  
Hong Zhu
Keyword(s):  
Cyclic Voltammetry ◽  
Emulsion Polymerization ◽  
Cobalt Oxide ◽  
Electrochemical Behavior ◽  
Electrochemical Impedance ◽  
X Ray Diffraction ◽  
Nano Composite ◽  
X Ray ◽  
Scan Rate ◽  
And Performance

Cobalt oxide-Polyaniline (Co3O4/PANI) nanocomposites were prepared via inverted emulsion polymerization. The structure of the obtained composites were characterized by X-ray diffraction (XRD). The electrochemical behavior was studied by cyclic voltammetry(CV) and electrochemical impedance spectrometry(EIS) experiments. The Co3O4/PANI(1:2) composite calcined at 400°C exhibits the highest capacitance value of 357 F/g at the scan rate of 5mV/s.

Control of the phase composition of advanced calcium phosphates using an x-ray diffractometer with a curved position-sensitive detector

2020 ◽  
Vol 86 (6) ◽  
pp. 29-35
Author(s):  
V. P. Sirotinkin ◽  
O. V. Baranov ◽  
A. Yu. Fedotov ◽  
S. M. Barinov
Keyword(s):  
Phase Composition ◽  
Calcium Phosphates ◽  
Position Sensitive Detector ◽  
Sensitive Detector ◽  
X Ray Diffraction ◽  
X Ray ◽  
Impurity Phases ◽  
Position Sensitive ◽  
Diffraction Peaks ◽  
Diffraction Patterns

The results of studying the phase composition of advanced calcium phosphates Ca10(PO4)6(OH)2, β-Ca3(PO4)2, α-Ca3(PO4)2, CaHPO4 · 2H2O, Ca8(HPO4)2(PO4)4 · 5H2O using an x-ray diffractometer with a curved position-sensitive detector are presented. Optimal experimental conditions (angular positions of the x-ray tube and detector, size of the slits, exposure time) were determined with allowance for possible formation of the impurity phases during synthesis. The construction features of diffractometers with a position-sensitive detector affecting the profile characteristics of x-ray diffraction peaks are considered. The composition for calibration of the diffractometer (a mixture of sodium acetate and yttrium oxide) was determined. Theoretical x-ray diffraction patterns for corresponding calcium phosphates are constructed on the basis of the literature data. These x-ray diffraction patterns were used to determine the phase composition of the advanced calcium phosphates. The features of advanced calcium phosphates, which should be taken into account during the phase analysis, are indicated. The powder of high-temperature form of tricalcium phosphate strongly adsorbs water from the environment. A strong texture is observed on the x-ray diffraction spectra of dicalcium phosphate dihydrate. A rather specific x-ray diffraction pattern of octacalcium phosphate pentahydrate revealed the only one strong peak at small angles. In all cases, significant deviations are observed for the recorded angular positions and relative intensity of the diffraction peaks. The results of the study of experimentally obtained mixtures of calcium phosphate are presented. It is shown that the graphic comparison of experimental x-ray diffraction spectra and pre-recorded spectra of the reference calcium phosphates and possible impurity phases is the most effective method. In this case, there is no need for calibration. When using this method, the total time for analysis of one sample is no more than 10 min.

Formation of nanoscale sodium dodecahydro-closo- dodecaborate Na2[B12H12] on silicate matrix surface

2019 ◽  
Vol 484 (1) ◽  
pp. 41-43
Author(s):  
E. A. Malinina ◽  
V. K. Skachkova ◽  
I. V. Kozerozhets ◽  
V. V. Avdeeva ◽  
L. V. Goeva ◽  
...  
Keyword(s):  
Phase Composition ◽  
Ammonium Salt ◽  
Liquid Glass ◽  
Silicate Matrix ◽  
X Ray Diffraction ◽  
X Ray ◽  
Salt Sample ◽  
Matrix Surface

The method of nanoscaled sodium dodecahydro-closo-dodecaborate Na2[B12H12] synthesis is presented. The composite is heated to 200°C to yield the desired product, forming with the introduction of triethyl- ammonium salt [Et3NH]2[B12H12] into the silicate matrix of a sodium liquid glass. The morphology and phase composition of the synthesized sample are studied through SEM and X-ray diffraction methods, in comparison to those of a standard salt sample Na2[B12H12]. Based on the obtained data, the sample under study is an amorphous composite, on the surface of which nanoscale crystals of Na2[B12H12] form.

Hydrophobic Ferrocene Derivatives as Potential Standards in Electrochemistry

1997 ◽  
Vol 62 (2) ◽  
pp. 185-198 ◽  
Author(s):  
Jaroslav Podlaha ◽  
Petr Štěpnička ◽  
Róbert Gyepes ◽  
Vladimír Mareček ◽  
Alexander Lhotský ◽  
...  
Keyword(s):  
Surface Tension ◽  
Cyclic Voltammetry ◽  
Redox Potential ◽  
Diffusion Coefficients ◽  
Carbon Electrodes ◽  
X Ray Diffraction ◽  
Ferrocene Derivatives ◽  
X Ray ◽  
Special Cases ◽  
As Solubility

Ferrocene (FcH) derivatives monosubstituted by palmitoyl (1), hexadecyl (2), 1-adamantoyl (3) or 1-adamantylmethyl (4) groups were sythesized and characterized by NMR, mass and 57Fe Mossbauer spectroscopy. The structure of 1-adamantoylferrocene was determined by single-crystal X-ray diffraction. Cyclic voltammetry on gold and glass-like carbon electrodes demonstrated that the compounds can serve as electrochemical standards for special cases since their ferrocene/ferricinium redox potential remains stable and reversible, while the properties such as solubility, diffusion coefficients and surface tension are strongly solvent-dependent.

scholarly journals Surfactant-free synthesis of carbon-supported silver (Ag/C) nanobars as an efficient electrocatalyst for alcohol tolerance and oxidation of sodium borohydride in alkaline medium

2021 ◽  
Vol 3 (6) ◽  
Author(s):  
Santanu Dey ◽  
Pradipta Chakraborty ◽  
Dhiraj Kumar Rana ◽  
Subhamay Pramanik ◽  
Soumen Basu
Keyword(s):  
Cyclic Voltammetry ◽  
Ethylene Glycol ◽  
Alkaline Medium ◽  
Sodium Borohydride ◽  
Metallic Silver ◽  
Alcohol Tolerance ◽  
Current Ratio ◽  
X Ray ◽  
Scan Rate ◽  
Borohydride Oxidation

AbstractWe have synthesized carbon-supported silver (Ag/C) nanobars by a simple surfactant-free hydrothermal method using glucose as the reducing reagent as well as the source of carbon in Ag/C nanobars. Physicochemical characterization of the materials was performed by X-ray Diffraction (XRD), field emission scanning electron microscopy, and energy-dispersive X-ray spectroscopy. The XRD pattern confirmed the presence of a pure metallic silver phase. No carbon phase was detected, which indicates that the carbon exists mainly in the amorphous form. The electrocatalytic activity of Ag/C in different electrolyte solutions such as 0.5 M NaOH, 0.5 M NaOH + 1 M ethanol (EtOH), 0.5 M NaOH + 1 M ethylene glycol (EG), and 0.5 M NaOH + 0.01 M NaBH4 (sodium borohydride) was studied by cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS), and chronoamperometry (CA) study. Alcohol tolerance of the catalysts was also established in the presence of ethanol and ethylene glycol. The forward-to-backward current ratio from cyclic voltammetry (CV) study of Ag/C-20 (20 h) in 0.5 M NaOH + 1 M ethanol solution at 100 mV s−1 scan rate is 4.13 times higher compared to that of Ag/C-5 (5 h). Hence, Ag/C-20 is a better candidate for the tolerance of ethanol. In the presence of ethylene glycol (1 M) in 0.5 M NaOH solution, it is obtained that the forward-to-backward current ratio at the same scan rate for Ag/C-20 is lower than that in the presence of ethanol. The durability of the catalyst was studied by chronoamperometry measurement. We studied the electrochemical kinetics of Ag/C catalysts for borohydride oxidation in an alkaline medium. The basic electrochemical results for borohydride oxidation show that Ag/C has very well strength and activity for direct borohydride oxidation in an alkaline medium. The reaction of borohydride oxidation with the contemporaneous BH4−. hydrolysis was noticed at the oxidized silver surface. Among all the synthesized Ag/C catalysts, Ag/C-20 exhibited the best electrocatalytic performance for borohydride oxidation in an alkaline medium. The activation energy and the number of exchange electrons at Ag/C-20 electrode surface for borohydride electro-oxidation were estimated as 57.2 kJ mol−1 and 2.27, respectively.

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