MESOPOROUS CARBON ELECTRODE: SYNTHESIS, CHARACTERIZATION AND ELECTROCHEMICAL PROPERTIES

2010 ◽  
Vol 03 (03) ◽  
pp. 161-164 ◽  
Author(s):  
XI LONG ◽  
CHUNXIA ZHAO ◽  
WEN CHEN
Keyword(s):  
Cyclic Voltammetry ◽  
Electrochemical Properties ◽  
Mesoporous Carbon ◽  
Nitrogen Adsorption ◽  
Mesoporous Structure ◽  
Constant Current ◽  
Surface Areas ◽  
Constant Current Charge ◽  
Adsorption Desorption ◽  
Charge Discharge

The present paper studies a kind of mesoporous carbon (MC) with high electrochemical performance, which was prepared by vapor infiltration method. The microstructure and electrochemical properties of the mesoporous carbon were investigated by transmission electron microscopy (TEM), nitrogen adsorption–desorption isotherms, cyclic voltammetry (CV), constant current charge–discharge cycling (CD), and the long-term stability test. The results indicated that the mesoporous carbon has an ordered mesoporous structure, with pore size of about 3.87 nm and surface areas of 1087 m2 ⋅ g-1. The cyclic voltammetry curve reveals typical electrical double-layer capacitor property. After 200 cycles, the CV curves can almost be overlapped, which indicates excellent cycling stability. From the charge/discharge cycling, the specific capacitance of MC is 117 F ⋅ cm-1 in 1.0 M KNO3 electrolyte media at a scan rate of 1.0 mV ⋅ s-1, which decays with increasing current density. The charge–discharge efficiency also decays with it.

scholarly journals SYNTHESIS AND ELECTROCHEMICAL PROPERTIES OF MESOPOROUS CARBON SUPPORTED WELL–DISPERSED COBALT OXIDES NANOPARTICLES

2018 ◽  
Vol 55 (1B) ◽  
pp. 230
Author(s):  
Nguyen Van Tu
Keyword(s):  
Electron Microscopy ◽  
Cobalt Oxide ◽  
Mesoporous Carbon ◽  
Good Control ◽  
Nitrogen Adsorption ◽  
Mesoporous Structure ◽  
Oxide Nanoparticles ◽  
Cobalt Oxide Nanoparticles ◽  
Transmission Electron ◽  
Adsorption Desorption

In this article, well–dispersed cobalt oxide nanoparticles supported on mesoporous carbon (CMK–3) have been successfully synthesized. The composites were characterized by field emission scanning electron microscopy, transmission electron microscopy, X–ray diffraction and nitrogen adsorption–desorption analysis. The results have confirmed that, at a cobalt loading of 15 wt%, the composites have not only retained mesoporous structure of the support but also shown a good control of dispersed cobalt oxide nanoparticles with size of ~4 nm. The electrochemical property tests for the synthesized samples have shown significant improvement compared to the blank carbon (CMK–3) without cobalt oxide incorporation.

Ruthenium Oxide/Activated Carbon Composites for Electrochemical Capacitors

2011 ◽  
Vol 347-353 ◽  
pp. 3370-3374
Author(s):  
Ming Dong Zheng ◽  
Ru Chun Li ◽  
Xiao Jun He ◽  
Xian Ping Dong ◽  
Ping Hua Ling ◽  
...  
Keyword(s):  
Activated Carbon ◽  
Ruthenium Oxide ◽  
Total Pore Volume ◽  
Nitrogen Adsorption ◽  
Micropore Volume ◽  
Constant Current ◽  
Composite Electrodes ◽  
Hno3 Solution ◽  
Constant Current Charge ◽  
Charge Discharge

Activated carbon (AC) was prepared from lignite by microwave heating ZnCl2. The pore structure parameters of AC are characterized by nitrogen adsorption technique. The AC and ruthenium oxide/AC composite are characterized by thermogravimetric analysis and transmission electron microscope. Electrochemical properties of ACs and ruthenium oxide/AC composite electrodes were investigated by cyclic voltammetry and constant current charge–discharge after AC was pre−oxidized by HNO3 solution. The results show that the specific surface area and total pore volume of AC from lignite reaches 1310 m2 g−1 and 0.80 cm3 g−1, respectively. The micropore volume of AC from lignite totals only 12.5%. AC and ruthenium oxide/AC composite electrodes with 5wt.% ruthenium oxide loading show high cycle stability. Compared to pristine AC electrode, specific capacitance of ruthenium/AC composite electrode and energy density of ruthenium/AC capacitor after 100 charge−discharge cycles increases 40.8% and 39.1%, respectively.

Synthesis and Electrochemical Properties of Porous Titania Fabricated from Nanosheets

2013 ◽  
Vol 566 ◽  
pp. 111-114 ◽  
Author(s):  
Mitsumasa Sakao ◽  
Norihito Kijima ◽  
Masashi Yoshinaga ◽  
Junji Akimoto ◽  
Takeshi Okutani
Keyword(s):  
Electrochemical Properties ◽  
Spray Drying ◽  
Active Material ◽  
Nitrogen Adsorption ◽  
Mesoporous Structure ◽  
Lithium Insertion ◽  
Lithium Cell ◽  
Porous Titania ◽  
Desorption Isotherms ◽  
Adsorption Desorption

A porous titania was synthesized by spray-drying of titania nanosheets exfoliated by (C4H9)4NOH. Nitrogen adsorption-desorption isotherms showed that the porous titania has a mesoporous structure composed of slit-shaped pores. The porous titania acted as a rechargeable active material in a liquid organic electrolyte lithium cell. An initial lithium insertion capacity was about 150 mAh/g (cut-off voltage of 1.0 V), which approximately correspond to the composition of Li0.45TiO2.

scholarly journals In Situ Recrystallization of Mesoporous Carbon–Silica Composite for the Synthesis of Hierarchically Porous Zeolites

Materials ◽  
2020 ◽  
Vol 13 (7) ◽  
pp. 1640 ◽  
Author(s):  
Jun Du ◽  
Yan Wang ◽  
Yan Wang ◽  
Ruifeng Li
Keyword(s):  
Mesoporous Carbon ◽  
Nitrogen Adsorption ◽  
Mesoporous Structure ◽  
Hierarchical Zeolites ◽  
Hierarchically Porous ◽  
Silica Composite ◽  
Crystallization Procedure ◽  
Cracking Reaction ◽  
Adsorption Desorption

Hierarchically porous ZSM-5 was prepared by utilizing a two-step crystallization procedure with carbon–silica composites as precursors. The hierarchically porous zeolites obtained a regular mesoporous structure with aluminum incorporated into the carbon–silica composite frameworks. The carbon–silica composite zeolites were characterized by XRD, TEM, SEM, and nitrogen adsorption/desorption. As-prepared hierarchical zeolites were used in the 1,3,5-triisopropylbenzene (TIPB) cracking reaction and exhibited significantly high TIPB conversion, while the accessibility factors were also determined.

Preparing composites of Ni–Al layered double hydroxide/graphene electrode for supercapacitors and their electrochemical properties

2020 ◽  
Vol 10 (8) ◽  
pp. 1364-1368 ◽  
Author(s):  
Yunlong Zhou ◽  
Dan Yu ◽  
Junwen Peng ◽  
Xiaofang Chen ◽  
Zhibiao Hu
Keyword(s):  
Cyclic Voltammetry ◽  
Electrochemical Properties ◽  
Layered Double Hydroxide ◽  
Electrochemical Impedance ◽  
Morphological Structure ◽  
Constant Current ◽  
Hydrothermal Route ◽  
Double Hydroxide ◽  
The Given ◽  
Charge Discharge

The composites of Ni–Al layered double hydroxide (Ni–Al LDH)/graphene (GR) had been synthesized through the hydrothermal route in this work. The mechanism of the composites depended on XRD. Meanwhile, SEM was used to record the morphological structure of the composites. The electrochemical properties were analyzed through the charge-discharge of constant current, cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS). The composites of Ni–Al LDH/GR possessed a layered structure and the structure was uniformly dispersed on the graphene. The given discharge capacity of the composites of Ni–Al LDH/GR was higher than the value of bare Ni–Al LDH, which was approximately 400 F · g–1 in the speed of 1 A g–1; Meanwhile, the capacitance retention was still more than 1 time higher compared with the value of Ni–Al LDH for 500 cycles at 1 A g–1.

scholarly journals Enhanced Photocatalytic Activity of Hierarchical Macro-Mesoporous Anatase byZrO2Incorporation

2012 ◽  
Vol 2012 ◽  
pp. 1-10 ◽  
Author(s):  
M. L. García-Benjume ◽  
M. I. Espitia-Cabrera ◽  
M. E. Contreras-García
Keyword(s):  
Photocatalytic Activity ◽  
Sol Gel ◽  
Nitrogen Adsorption ◽  
Mesoporous Structure ◽  
Tween 20 ◽  
X Ray Diffraction ◽  
Surface Areas ◽  
Photocatalytic Effect ◽  
Different Temperatures ◽  
Adsorption Desorption

The effect of the addition of zirconia in the photocatalytic behaviour of titania is analysed. In order to increase the ways for reagent and product diffusion in the material, a sol-gel hydrothermal synthesis route using Tween-20 as a directing agent to obtain a hierarchical macro-mesoporous structure is proposed. Nanostructured macro-mesoporous TiO2/ZrO2photocatalyst with 0, 10, 20, 30, and 100% mol of ZrO2were obtained and calcined at different temperatures. The crystalline structure was analyzed by X-ray diffraction and TEM. The porosity was confirmed by SEM, TEM, and nitrogen adsorption-desorption isotherms. The worm-like mesoporous structure was confirmed by TEM. The specific surface areas obtained by Brunauer-Emmet-Teller method (BET) ranged from 125 to 180 m2/g. The Tween-20 total elimination from the structure by thermal treatment was confirmed by infrared spectroscopy and thermogravimetric analysis. Additionally, the photocatalytic effect of the zirconia addition was studied in the methylene blue (MB) degradation reaction, and the best photocatalytic activity was obtained in the sample with 10% mol of ZrO2, degrading up to 92% the MB.

Influence of Chemical Modification of Activated Carbon Surface on Performance of Supercapacitors

2012 ◽  
Vol 455-456 ◽  
pp. 427-429
Author(s):  
Mei Gen Deng ◽  
Ren Qing Wang
Keyword(s):  
Cyclic Voltammetry ◽  
Activated Carbon ◽  
Chemical Modification ◽  
Constant Current ◽  
Carbon Surface ◽  
Contribution Rate ◽  
Ftir Studies ◽  
Constant Current Charge ◽  
A Current ◽  
Charge Discharge

In order to improve capacitance in supercapacitors application, activated carbon (AC) was modified by nitric acid oxidizing treatment. Oxygen-containing functional groups (OCFG) were detected by using FTIR techniques. Cyclic voltammetry and constant current charge-discharge were used to characterize the electrochemical performance of the samples in 6 mol/L KOH solution. FTIR studies showed that chemical modification promoted the formation of OCFG on the surface of AC. It was found that the contribution rate of pseudo-capacitance to the total capacitance increased significantly with the extent of oxidization treatment. When oxidized by 50% HNO3, AC achieved a specific capacitance of 197.26F/g at a current density of 20mA/cm2 corresponding to an increasing rate up to 20%.

scholarly journals Zn-Doped LiNi1/3Co1/3Mn1/3O2Composite as Cathode Material for Lithium Ion Battery: Preparation, Characterization, and Electrochemical Properties

2015 ◽  
Vol 2015 ◽  
pp. 1-5 ◽  
Author(s):  
Han Du ◽  
Yuying Zheng ◽  
Zhengjie Dou ◽  
Hengtong Zhan
Keyword(s):  
Cathode Material ◽  
Electrochemical Properties ◽  
Sol Gel ◽  
Lithium Ion ◽  
Constant Current ◽  
Electrode Polarization ◽  
X Ray Diffraction ◽  
Initial Charge ◽  
Constant Current Charge ◽  
Charge Discharge

Zn-doped LiNi1/3Co1/3Mn1/3O2composite, Li(Ni1/3Co1/3Mn1/3)1–xZnxO2(x= 0.02; 0.05; 0.08), is synthesized by the sol-gel method. The crystal structure, morphology, and electrochemical performance are investigated via X-ray diffraction (XRD), scanning electron microscope (SEM), cyclic voltammetry (CV), and constant current charge/discharge experiment. The result reveals that Zn-doping cathode material can reach the initial charge/discharge capacity of 188.8/162.9 mAh·g−1for Li(Ni1/3Co1/3Mn1/3)0.98Zn0.02O2and 179.0/154.1 mAh·g−1for Li(Ni1/3Co1/3Mn1/3)0.95Zn0.05O2with the high voltage of 4.4 V at 0.1 C. Furthermore, the capacity retention of Li(Ni1/3Co1/3Mn1/3)0.98Zn0.02O2is 95.1% at 0.5 C after 50 cycles at room temperature. The improved electrochemical properties of Zn-doped LiNi1/3Co1/3Mn1/3O2are attributed to reduced electrode polarization, enhanced capacity reversibility, and excellent cyclic performance.

Preparation and Electrochemical Properties of LaMnO3 Powder as a Supercapacitor Electrode Material

2017 ◽  
Vol 727 ◽  
pp. 698-704 ◽  
Author(s):  
Xian Wei Wang ◽  
Xiao Er Wang ◽  
Hui Chao Zhang ◽  
Qian Qian Zhu ◽  
Dong Li Zheng ◽  
...  
Keyword(s):  
Cyclic Voltammetry ◽  
Electrochemical Properties ◽  
Electrode Material ◽  
Raw Materials ◽  
Sol Gel ◽  
Galvanostatic Charge ◽  
Supercapacitor Electrode ◽  
Lanthanum Manganate ◽  
Pure Phase ◽  
Charge Discharge

The structural and electrochemical properties of lanthanum manganate (LaMnO3) powder prepared by the sol-gel method are researched in this article. The powder calcined at 600 °C showed amorphous, and the powder calcined at 700-800 °C showed the pure phase of the LaMnO3. The grains with the size of about 80-120 nm were agglomerating together. Cyclic voltammetry and galvanostatic charge-discharge were used to characterize the electrochemical properties in alkaline environment. The electrochemical properties calcined at 700 °C showed a specific capacitance of 73 F/g at the current density of 0.5 A/g. The raw materials for preparing the LaMnO3 powder are cheap, and the operation method is simple.

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