Ordered Macroporous Carbon/Polyaniline Nanocomposites as Electrode Materials for Supercapacitors

2012 ◽  
Vol 722 ◽  
pp. 25-30
Author(s):  
Su Yan Qiao ◽  
Li Zhen Fan
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Electrochemical Properties ◽  
Electrode Materials ◽  
Galvanostatic Charge ◽  
Ordered Macroporous ◽  
A Current ◽  
Macroporous Carbon ◽  
Charge Discharge ◽  
Scanning Electron

Polyaniline (PANI) and ordered macroporous carbon (C80) composites were prepared via a simple and speedy polymerization of aniline in the presence of C80. The effect of PANI content on the electrochemical properties was studied in detail. The morphologies were manifested through field emission scanning electron microscopy (FE-SEM), and the electrochemical properties were investigated by cyclic voltammetry (CV), galvanostatic charge-discharge and impedance in 1 mol/L H2SO4. The results indicate that the polymerization of aniline occurred in the pores of carbon, and as the aniline content increased, more polyaniline was synthesized in the pores. When the PANI content was 43 wt%, the specific capacitance of the composite was as high as 368.7 F/g at a current density of 0.06 A/g, which was 2.6 times higher than that of the host C80 (140 F/g).

Synthesis and Electrochemical Properties of Macro-/Microporous Carbon Foams

2011 ◽  
Vol 239-242 ◽  
pp. 1396-1399 ◽  
Author(s):  
Wei Xiong ◽  
Ming Xian Liu ◽  
Li Hua Gan ◽  
Xiao Gang Wang ◽  
Zi Jie Xu ◽  
...  
Keyword(s):  
Electrochemical Properties ◽  
Electrode Materials ◽  
Microporous Carbon ◽  
Pore Channel ◽  
Diffusion Resistance ◽  
Galvanostatic Charge ◽  
Pore Size Distributions ◽  
Carbon Foams ◽  
Macroporous Carbon ◽  
Charge Discharge

In this paper, we demonstrated the synthesis and electrochemical properties of macro-/ microporous carbon foams (MMCFs) for application as supercapacitor electrode materials. By using Span 80 and Tween 80 as emulsifiers, resorcinol/formaldehyde solution as aqueous phase, and 1iquid paraffin as oil phase, an O/W emulsion was obtained. Macroporous carbon foams were prepared by the polymerization of the emulsion, followed by drying and carbonization. The macroporous carbon foams then were activated at 1273 K by using KOH as an activated agent to obtain MMCFs. The resultant MMCFs were characterized by scanning electron microscopy (SEM) and Brunauer-Emmett-Teller (BET) analyzer. The results indicate that the MMCFs have specific surface areas of 529-670 m2/g, total pore volumes of 0.27-0.33 cm3/g and possess dual pore size distributions with macropore sizes of 0.5-5.0 μm and micropore sizes of 1.72-1.86 nm dependent on the specific experiment parameters. The hierarchical pore structure is propitious to decreases the diffusion resistance of electrolyte and accelerate the ion transfer within the pore channel, and thus improve the electrochemical properties of MMCFs. The electrochemical properties of the MMCFs have been investigated by cyclic voltammetry (CV) and galvanostatic charge-discharge with a three-electrode system in electrolyte of 6 mol/L KOH solution. The CV curves of the MMCFs show quite rectangular curve shape without observation of obvious oxidation-reduction evolution peaks, suggesting a typical nonfaradic adsorption/desorption reaction. The MMCFs present linear galvanostatic charge-discharge curve under the current densities of 1.0-4.0 A/g and their specific capacitance values are 89-110 F/g. The MMCFs has good electrochemical performance and they are good candidates as electrode materials for supercapacitors.

Effects of Mg2+ Doping on the Properties of LiFePO4 Synthesized via Hydrothermal Route

2009 ◽  
Vol 610-613 ◽  
pp. 498-501
Author(s):  
Guang Chuan Liang ◽  
Xiao Ke Zhi ◽  
Xiu Qin Ou ◽  
Li Wang
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Hydrothermal Synthesis ◽  
Cell Volume ◽  
X Ray Diffraction ◽  
Hydrothermal Route ◽  
X Ray ◽  
Charge Discharge ◽  
Scanning Electron ◽  
Discharge Test

Mg2+ doped LiFePO4 was synthesized from Li3PO4, FeSO4 and MgSO4 by a hydrothermal synthesis at 150 °C（Li1-xMgxPO4, x=0.00, 0.01,0.02,0.04,0.06）. The samples were characterized with X-ray diffraction (XRD), scanning electron microscopy (SEM) and charge-discharge test. The results showed that Mg2+ dissolved in the LiFePO4 lattice. When the content is in the range of 0 to 6 mol%, Mg2+ caused the shrinkage of LiFePO4 cell volume. The capacity of doped and undoped samples at low discharging rate was similar, about 145mAhg-1 for 0.2C. But the sample doped with 2-4 mol% Mg2+ has higher capacity and longer cycle lifetime than the undoped one at 5C.

Microstructure and Electrochemical Properties of Foamed Ni-Mo Alloy by Pulse-Electrodeposition

2011 ◽  
Vol 305 ◽  
pp. 378-383 ◽  
Author(s):  
Hong Xu ◽  
Ning Li ◽  
Wei Zeng Chen ◽  
Bao De Jing
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Corrosion Resistance ◽  
Electrochemical Properties ◽  
Alkaline Solution ◽  
Electrodeposition Technique ◽  
X Ray ◽  
Pulsed Electrodeposition ◽  
Scanning Electron ◽  
Skeleton Structure

A variety of foamed Ni-Mo alloys coatings have been obtained using pulsed electrodeposition technique. The deposit is mainly composed of amorphous structural through the X-ray diffractions (XRD), the morphology clearly contains large amounts of multi-bubble pore structure with pentagonal or hexagonal skeleton structure and obviously stratifys through scanning electron microscopy (SEM) experimentals. This pentagonal or hexagonal skeleton structure and obvious stratification has a larger surface area. The electrolysis experiments show that such foamed alloys have a low hydrogen evolution overpotential and a better corrosion resistance in 25°C, 7mol·L-1 KOH alkaline solution.

Graphene Oxide Nanoplate-MnO2 Composites for Supercapacitors

2012 ◽  
Vol 512-515 ◽  
pp. 944-947 ◽  
Author(s):  
Jia Wei Deng ◽  
Huan Pang ◽  
Shao Mei Wang ◽  
Jiang Shan Zhang
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Cyclic Voltammetry ◽  
Graphene Oxide ◽  
Ambient Temperature ◽  
Electrochemical Properties ◽  
Electrode Material ◽  
Supercapacitor Electrode ◽  
Scanning Electron

Graphene oxide nanoplate-MnO2composites have been synthesized by oxidizing part of the carbon atoms in the framework of graphene oxide nanoplates at ambient temperature. The composites were characterized by scanning electron microscopy (SEM) and cyclic voltammetry (CV). Their microstructures and morphologies have affected their electrochemical properties. Compared with MnO2nanoparticles, the nanocomposite prepared reveals better electrochemical properties as a supercapacitor electrode material.

Double Templating Synthesis and Electrochemical Properties of Carbon Foams

2011 ◽  
Vol 347-353 ◽  
pp. 3400-3403
Author(s):  
Yang Li ◽  
Ming Xian Liu ◽  
Li Hua Gan ◽  
Liang Yang ◽  
Zi Jie Xu ◽  
...  
Keyword(s):  
Electrochemical Properties ◽  
Pore Size ◽  
Electrode Materials ◽  
Soft Template ◽  
Electrochemical Performances ◽  
Galvanostatic Charge ◽  
Hard Template ◽  
Pore Size Distributions ◽  
Carbon Foams ◽  
Charge Discharge

In this paper, we demonstrated the synthesis and electrochemical properties of carbon foams for use as supercapacitor electrode materials. Carbon foams were prepared by double templating method in which emulsion and nanosilica were used as soft template and hard template, respectively. By using Span 80 and Tween 80 as emulsifiers, resorcinol/formaldehyde aqueous solution which contained nanosilica as aqueous phase and 1iquid paraffin as oil phase, an O/W emulsion was obtained. Carbon foams were obtained by emulsion polymerization, carbonization and the subsequent removal of the hard template. The as-prepared carbon foams were characterized by scanning electron microscopy (SEM), Brunauer-Emmett-Teller (BET) analyzer, and electrochemical workstation. The results indicate that the resultant carbon foams have specific surface area of 160 m2/g, total pore volume of 0.15 cm3/g and possess dual pore size distributions with macropore sizes of 0.5-2.0 μm and the most probable pore size of 4.1 nm. The electrochemical properties of the carbon foams have been investigated by cyclic voltammetry (CV) and galvanostatic charge- discharge with a three-electrode system in electrolyte of 6 mol/L KOH solution. The CV curves of the carbon foams show rectangular-like shape without obvious oxidation-reduction evolution peak, which suggests a typical nonfaradic adsorption/desorption reaction. The carbon foams present linear galvanostatic charge-discharge curve under the current densities of 1.0-5.0 A/g and their specific capacitance values are 60-90 F/g. The good electrochemical performances of carbon foams would provide candidate as electrode materials for supercapacitors.

Synthesis and Electrochemical Performance of Poly(N-Acetylaniline)/Carbon Nanotubes Composite for Supercapacitors

2011 ◽  
Vol 694 ◽  
pp. 315-318
Author(s):  
Jing Li ◽  
Hua Qing Xie ◽  
Yang Li ◽  
Ji Fen Wang
Keyword(s):  
Carbon Nanotubes ◽  
Electrochemical Method ◽  
Cycle Stability ◽  
Galvanostatic Charge ◽  
Maximum Capacity ◽  
Multi Walled Carbon Nanotubes ◽  
Walled Carbon Nanotubes ◽  
A Current ◽  
Charge Discharge ◽  
Scanning Electron

Poly(N-acetylaniline)/multi-walled carbon nanotubes composite (PAANI/MWCNTs) are synthesized using electrochemical method. The morphology of the composite is examined by scanning electron microscopy. Electrochemical properties are characterized by cyclic voltammetry and galvanostatic charge/discharge. A remarkable specific capacitance of 690 F g-1 is obtained at a current density of 2.5 A g-1, compared to 225 F g-1 for pure PAANI and 90 F g-1 for MWCNTs. The composite presents excellent cycle stability, losing 15% of the maximum capacity after 1000 cycles.

scholarly journals Preparation and Electrochemical Properties of C/LiMnPO4 for Lithium-Ion Battery by Spray Pyrolysis

2010 ◽  
Vol 445 ◽  
pp. 95-99
Author(s):  
Yuichi Suetsugu ◽  
Atsushi Hujita ◽  
Takayuki Kodera ◽  
Takashi Ogihara
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Citric Acid ◽  
Electrochemical Properties ◽  
Spray Pyrolysis ◽  
Lithium Ion ◽  
Cycle Performance ◽  
Olivine Structure ◽  
First Discharge Capacity ◽  
Scanning Electron

Spherical C/LiMn1-XMXPO4 (M=Mg, Zn) cathode materials were successfully prepared by spray pyrolysis. An olivine structure was obtained by heating at 973 K under argon/hydrogen (5%) atmosphere. Citric acid was used as the carbon source. Scanning electron microscopy (SEM) showed that the materials had spherical morphology. The electrochemical properties of the cathode were also estimated by the rechargeable capacity and cycle performance. The first discharge capacity of C/LiMn1-XZnXPO4 (X = 0.1) was approximately 60 mAh/g　at 0.1 C.

scholarly journals Nanofiber NiMoO4/g-C3N4 Composite Electrode Materials for Redox Supercapacitor Applications

Nanomaterials ◽  
2020 ◽  
Vol 10 (2) ◽  
pp. 392 ◽  
Author(s):  
Kannadasan Thiagarajan ◽  
Thirugnanam Bavani ◽  
Prabhakarn Arunachalam ◽  
Seung Jun Lee ◽  
Jayaraman Theerthagiri ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Electrode Material ◽  
Composite Electrode ◽  
Electrode Materials ◽  
Electrochemical Impedance ◽  
Galvanostatic Charge ◽  
Transmission Electron ◽  
Cd Studies ◽  
Supercapacitor Applications ◽  
Charge Discharge

NiMoO4/g-C3N4 was fabricated by a hydrothermal method and used as an electrode material in a supercapacitor. The samples were characterized by XRD, FTIR, scanning electron microscopy (SEM) and transmission electron microscopy (TEM) to study the physical and structural properties of the as-prepared NiMoO4/g-C3N4 material. The electrochemical responses of pristine NiMoO4 and the NiMoO4/g-C3N4 nanocomposite material were investigated by cyclic voltammetry (CV), galvanostatic charge-discharge (GCD) and electrochemical impedance spectroscopy (EIS). From the CD studies, the NiMoO4/g-C3N4 nanocomposite revealed a higher maximum specific capacitance (510 Fg−1) in comparison to pristine NiMoO4 (203 Fg−1). In addition, the NiMoO4/g-C3N4 composite electrode material exhibited high stability, which maintained up to 91.8% capacity even after 2000 charge-discharge cycles. Finally, NiMoO4/g-C3N4 was found to exhibit an energy density value of 11.3 Whkg−1. These findings clearly suggested that NiMoO4/g-C3N4 could be a suitable electrode material for electrochemical capacitors.

Sign in / Sign up

Export Citation Format

Share Document