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1.
Electrochemical capacitance of nickel oxide nanotubes synthesized in anodic aluminum oxide templates
Juan Xu Lan Gao Jianyu Cao Wenchang Wang Zhidong Chen 《Journal of Solid State Electrochemistry》2011,15(9):2005-2011
Nickel oxide (NiO) nanotubes for supercapacitors were synthesized by chemically depositing nickel hydroxide in anodic aluminum
oxide templates and thermally annealing at 360 °C. The synthesized nanotubes have been characterized by scanning electron
microscopy, transmission electron microscopy, and X-ray diffraction. The capacitive behavior of the NiO nanotubes was investigated
by cyclic voltammetry, galvanostatic charge–discharge experiment, and electrochemical impedance spectroscopy in 6 M KOH. The
electrochemical data demonstrate that the NiO nanotubes display good capacitive behavior with a specific capacitance of 266 F g−1 at a current density of 0.1 A g−1 and excellent specific capacitance retention of ca. 93% after 1,000 continuous charge–discharge cycles, indicating that the
NiO nanotubes can become promising electroactive materials for supercapacitor. 相似文献
2.
Zhang Fang Jiang Jianwei Yuan Changzhou Hao Liang Shen Laifa Zhang Luojiang Zhang Xiaogang 《Journal of Solid State Electrochemistry》2012,16(5):1933-1940
Nanostructured Co
x
Ni1−x
–Al layered triple hydroxides (Co
x
Ni1−x
–Al LTHs) have been successfully synthesized by a facile hydrothermal method using glycine as chelating agent. The samples
were characterized by X-ray diffraction, thermogravimetry, Fourier transform infrared spectroscopy and scanning electron microscopy.
The morphologies of Co
x
Ni1−x
–Al LTHs varied with the Co content and its effect on the electrochemical behavior was studied by cyclic voltammetry and galvanostatic
charge–discharge techniques. Electrochemical data demonstrated that the Co
x
Ni1−x
–Al LTHs with Co/Ni molar ratio of 3:2 owned the best performance and delivered a maximum specific capacitance of 1,375 F g−1 at a current density of 0.5 A g−1 and a good high-rate capability. The capacitance retained 93.3% of the initial value after 1,000 continuous charge–discharge
cycles at a current density of 2 A g−1. 相似文献
3.
Xiaoying Xie Wenwen Liu Luyang Zhao Chengde Huang 《Journal of Solid State Electrochemistry》2010,14(9):1585-1594
Manganese–vanadium oxide had been synthesized by a novel simple precipitation technique. Scanning electron microscopy, X-ray
diffraction, Brunauer–Emmett–Teller, thermogravimetric analysis/differential scanning calorimetry, and X-ray photoelectron
spectroscopy were used to characterize Mn–V binary oxide and δ-MnO2. Electrochemical capacitive behavior of the synthesized Mn–V binary oxide and δ-MnO2 was investigated by cyclic voltammetry, galvanostic charge–discharge curve, and electrochemical impedance spectroscope methods.
The results showed that, by introducing V into δ-MnO2, the specific surface area of the mixed oxide increased due to a formation of small grain size. The specific capacitance
increased from 166 F g−1 estimated for MnO2 to 251 F g−1 for Mn–V binary oxide, and the applied potential window extended to −0.2–1.0 V (vs. saturated calomel electrode). Through
analysis, it is suggested that the capacitance performance of Mn–V binary oxide materials may be improved by changing the
following three factors: (1) small grain and particle size and large activity surface area, (2) appropriate amount of lattice
water, and (3) chemical state on the surface of MnO2 material. 相似文献
4.
Changzhou Yuan Long Yang Linrui Hou Diankai Li Laifa Shen Fang Zhang Xiaogang Zhang 《Journal of Solid State Electrochemistry》2012,16(4):1519-1525
A facile hydrothermal strategy was first proposed to synthesize flower-like Co(OH)2 hierarchical microspheres. Further physical characterizations revealed that the flower-like Co(OH)2 microspherical superstructures were self-assembled by one-dimension nanobelts with rich mesopores. Electrochemical performance
of the flower-like Co(OH)2 hierarchical superstructures were investigated by cyclic voltammgoram, galvanostatic charge–discharge and electrochemical
impedance spectroscopy in 3 M KOH aqueous electrolyte. Electrochemical data indicated that the flower-like Co(OH)2 superstructures delivered a specific capacitance of 434 F g−1 at 10 mA cm−2 (about 1.33 A g−1), and even kept it as high as 365 F g−1 at about 5.33 A g−1. Furthermore, the SC degradation of about 8% after 1,500 continuous charge–discharge cycles at 5.33 A g−1 demonstrates their good electrochemical stability at large current densities. 相似文献
5.
Yanhua Li Kelong Huang Dongming Zeng Suqin Liu Zufu Yao 《Journal of Solid State Electrochemistry》2010,14(7):1205-1211
RuO2/Co3O4 thin films with different RuO2 content were successfully prepared on fluorine-doped tin oxide coated glass plate substrates by spray pyrolysis method, and
their capacitive behavior was investigated. Electrochemical property was performed by cyclic voltammetry, constant current
charge/discharge, and electrochemical impedance spectra. The capacitive performance of RuO2/Co3O4 thin films with different RuO2 content corresponded to a contribution from a main pseudocapacitance and an additional electric double-layer capacitance.
The specific capacitance of pure Co3O4, 15.5%, 35.6%, and 62.3% RuO2 composites at the current density of 0.2 A g−1 were 394 ± 8, 453 ± 9, 520 ± 10, and 690 ± 14 F g−1, respectively; 62.3% RuO2 composite presented the highest specific capacitance value at various current densities, whereas 35.6% RuO2 composite exhibited not only the largest specific capacitance contribution from RuO2 (C
sp
RuO2) at the current density of 0.5, 1.0, 1.5, and 2.0 A g−1 but also the highest specific capacitance retention ratio (46.3 ± 2.8%) at the current density ranging from 0.2 to 2.0 A g−1. Electrochemical impedance spectra showed that the contact resistance dropped gradually with the decrease of RuO2 content, and the charge-transfer resistance (R
ct) increased gradually with the decrease of RuO2 content. 相似文献
6.
Salimi Abollah Noorbakhsh Abdollah Semnani Abolfazl 《Journal of Solid State Electrochemistry》2011,15(9):2041-2052
A simple method was used to fabricate flavin adenine dinucleotide (FAD)/NiOx nanocomposite on the surface of glassy carbon
(GC) electrode. Cyclic voltammetry technique was applied for deposition nickel oxide nanostructures onto GC surface. Owing
to its high biocompatibility and large surface area of nickel oxide nanomaterials with immersing the GC/NiOx-modified electrode
into FAD solution for a short period of time, 10–140 s, a stable thin layer of the FAD molecules immobilized onto electrode
surface. The FAD/NiOx films exhibited a pair of well-defined, stable, and nearly reversible CV peaks at wide pH range (2–10).
The formal potential of adsorbed FAD onto nickel oxide nanoparticles film, E
o′ vs. Ag/AgCl reference electrode is −0.44 V in pH 7 buffer solutions was similar to dissolved FAD and changed linearly with
a slope of 58.6 mV/pH in the pH range 2–10. The surface coverage and heterogeneous electron transfer rate constant (k
s
) of FAD immobilized on NiOx film glassy carbon electrode are 4.66 × 10−11 mol cm−2 and 63 ± 0.1 s−1, indicating the high loading ability of the nickel oxide nanoparticles and great facilitation of the electron transfer between
FAD and nickel oxide nanoparticles. FAD/NiOx nanocomposite-modified GC electrode shows excellent electrocatalytic activity
toward S2O82− reduction at reduced overpotential. Furthermore, rotated modified electrode illustrates good analytical performance for amperometric
detection of S2O82−. Under optimized condition, the concentration calibration range, detection limit, and sensitivity were 3 μM–1.5 mM, 0.38 μM
and 16.6 nA/μM, respectively. 相似文献
7.
Svetlana Lichušina Ala Chodosovskaja Konstantinas Leinartas Algirdas Selskis Eimutis Juzeliūnas 《Journal of Solid State Electrochemistry》2010,14(9):1577-1584
Two approaches—substrate nanostructuring and incorporation of sulfide—were studied with the aim to increase electrochemical
capacitance of cobalt (hydro)oxide. A fiber structure of cobalt was deposited electrochemically with the fibers in the order
of tens of nanometers in thickness and hundreds of nanometers in length. Cobalt hydroxide film was formed on the nanostructured
substrate by anodic polarization in an alkaline solution. The hydroxide formation and its electrochemical capacitance have
been studied by cyclic voltammetry in conjunction with the electrochemical quartz crystal microbalance (EQCM). An irreversible
behavior was typical of the first anodic polarization cycle; it turned gradually to a reversible one during subsequent cycling.
EQCM measurements indicated exponential electrode mass growth during the first cycle, with subsequent transition to a quasipassive
state. The redox transitions Co(II) → Co(III) → Co(IV), which determine pseudocapacitance, did not cause remarkable electrode
mass change. The electrochemical capacitance of the nanofiber sample was found up to five times higher when compared to that
formed on conventional cobalt (abraded surface). Specifics of “per 1 g” evaluation of capacitance performance is discussed.
Measurements showed that about 10% of the entire hydroxide structure took part in the capacitive process. The capacitance
value determined per 1 g of active Co(OH)2 was in agreement with the limiting value predicted by the Faraday’s law (2,421 F g−1) sulfide-enhanced system with 18% CoS exhibited up to three times higher capacitance when compared to that of the sulfide-free
counterpart. The system shows promise for practical applications due to its low cost and technical simplicity. 相似文献
8.
C. Lucas I. Eiroa M. R. Nunes P. A. Russo M. M. L. Ribeiro Carrott M. I. da Silva Pereira M. E. Melo Jorge 《Journal of Solid State Electrochemistry》2009,13(6):943-950
The electrochemical properties of Ca1 − x
Ce
x
MnO3 perovskite-type oxide electrode have been investigated by cyclic voltammetry in Na2SO4 aqueous solutions with pH 14. The structural and morphological characterizations have also been investigated and the information
used to interpret the electrochemical behavior. An estimation of the electrode’s capacitance and roughness factor has been
obtained by means of cyclic voltammetry. The specific capacitance and consequently the roughness factor values are affected
by the presence of Ce ions in the oxide. These findings are in agreement with the increase of the oxide-specific surface area
by the introduction of Ce ion. The open-circuit potential and the voltammetric patterns are dependent on the presence of Ce
ion in the electrodes and support that the surface electrochemistry of the perovskite oxide electrodes is governed by the
Mn4+–Mn3+ redox couple. 相似文献
9.
Liangyu Gong Xiaohong Liu Linghao Su Longqiang Wang 《Journal of Solid State Electrochemistry》2012,16(1):297-304
A novel approach is developed to synthesize Co3O4 nanoparticles utilizing sawdust as a bio-template. Sawdust was first infiltrated with cobalt dichloride aqueous solution,
and then, in situ precipitation reaction took place when different precipitators (NaOH or H2C2O4) were added. Finally, the precursors, Co(OH)2 and CoC2O4, were calcined to produce the final Co3O4 nanoparticles and the template was removed simultaneously. The structure and morphology of the obtained products were characterized
by X-ray diffraction, Fourier transform infrared spectroscopy, and transmission electron microscopy. The observations revealed
the formation of cubic phase Co3O4 with the average diameter of about 40 and 60 nm, respectively. Their electrochemical properties were investigated by cyclic
voltammetry and galvanostatic charge–discharge tests. The highest specific capacitance of 289.7 F g−1 for the obtained Co3O4 electrode was obtained even at a discharge current of 20 mA after the 100th cycle and it increased by about 4% after the
1,000th cycle, demonstrating good electrochemical stability of such electrode materials. 相似文献
10.
A novel electrochemical sensor for methyl parathion based on silicate– cetyltrimethylammonium bromide nanocomposite film has
been fabricated by electro-assisted deposition onto glassy carbon electrode in one-step via an electrochemical modulation
of pH at the electrode/solution interface to promote controlled gelification of tetraethylorthosilicate sol, and was characterized
with scanning electron microscopy, X-ray diffraction, and electrochemical impedance spectroscopy. The electrochemical sensing
of methyl parathion on the film-modified electrode was investigated applying cyclic voltammetry and square wave voltammetry.
Compared to the unmodified electrode, the shapes of the redox peaks were improved and the peak currents significantly increased.
Experimental parameters such as deposition time, pH value, and accumulation conditions have been optimized. A linear relationship
between the peak current and methyl parathion concentration was obtained in the range from 1.0 × 10−7 to 1.0 × 10−4 mol L−1 with a detection limit of 1.04 × 10 −8 mol L−1 (S/N = 3) after accumulation at 0 V for 120 s. The film electrode shows great promise for determination of methyl parathion in
real samples.
相似文献
11.
R. Chandrasekaran Y. Soneda J. Yamashita M. Kodama H. Hatori 《Journal of Solid State Electrochemistry》2008,12(10):1349-1355
The effect of polymer–salt addition in the activated carbon electrode for electric double-layer capacitor (EDLC) has been
investigated. A series of composite thin film electrode consisting of activated carbon, carbon black, polytetrafluoroethylene
and polymer–salt complex (polyethyleneoxide–LiClO4) with an appropriate weight ratio were prepared and examined their performance for EDLCs using 1 mol L−1 LiClO4 in ethylene carbonate:diethylcarbonate electrolyte solution. The electrochemical capacitance performances of these electrodes
with different compositions were characterized by cyclic voltammetry, galvanostatic charge–discharge cycling, and AC impedance
measurements. By comparison, the best results were obtained with a composite electrode rich in polymer–salt additive (132 F
g−1 at 100 mA g−1 of galvanostatic experiment). In general, the polymer–salt-containing electrode had shown improved performance over activated
carbon electrodes without polymer–salt at high current density. 相似文献
12.
通过静电纺丝法制备Mn~(4+)掺杂的Co_3O_4复合纳米纤维,利用XRD、XPS、BET、SEM和电化学工作站等对材料的结构、成分、形貌和电化学性能进行表征与测试。研究发现,通过Mn~(4+)掺杂,Co_3O_4复合纳米纤维的电化学性能得到明显改善。当nCo∶nMn=20∶2时,相应的复合纤维具有较大比表面积68 m2·g-1,而且该样品呈现出清晰的氧化还原峰,在1 A·g-1的电流密度下,放电比电容量为585 F·g-1,这比纯Co_3O_4纳米纤维的416 F·g-1,有显著提高;循环500圈电容保持率达到82.6%,而纯Co_3O_4纳米纤维则是76.4%。 相似文献
13.
A novel nanocomposite of Co(OH)2−Ni(OH)2 and ultrastable Y molecular sieves was synthesized by an improved chemical precipitation method for electrochemical capacitors.
The Co(OH)2−Ni(OH)2/ultrastable Y zeolite (USY) composite and its microstructure were characterized by scanning electron microscopy, transmission
electron microscopy, and X-ray diffraction. Electrochemical characterization was performed by cyclic voltammetry and galvanostatic
charge–discharge measurements. The results show that Co(OH)2−Ni(OH)2/USY microstructure applied for the electrochemical energy storage has displayed superior capacitive performance. The effect
of heat treatment conditions on specific capacitance properties was also systemically explored. Upon annealing at 250 °C,
the maximum specific capacitance was up to 479 F/g (or 1,710 F/g after correcting for the weight percent of Co(OH)2−Ni(OH)2 phase). Annealing temperatures higher than 250 °C may cause the hydroxide to form oxide phase and decrease the surface activity
of the oxide, thereby leading to a decline of the specific capacitance. 相似文献
14.
Regular hexagonal Co–Al layered double hydroxides (Co–Al LDH) were synthesized by urea-induced homogeneous precipitation.
This material proved to be nanosheets by scanning electron microscopy and X-ray diffraction measurements. The electrochemical
capacitive behavior of the nanosheets in 1 M KOH solution were evaluated by constant current charge/discharge and cyclic voltammetric
measurements, showing a large specific capacitance of 192 F·g−1 even at the high current density of 2 A·g−1. When multiwall carbon nanotubes (MWNTs) were mixed with the Co–Al LDH, it was found that the specific capacitance and long-life
performance of all composite electrodes at high current density are superior to pure LDH electrode. When the added MWNTs content
is 10 wt%, the specific capacitance increases to 342.4 F·g−1 and remains at a value of 304 F·g−1 until the 400th cycle at 2 A·g−1, showing that this is a promising electrode material for supercapacitors working at heavy load. According to the electrochemical
impedance spectra, MWNTs greatly increase the electronic conductivity between MWNTs and the surface of Co–Al LDH, which consequently
facilitates the access of ions in the electrolyte and electrons to the electrode/electrolyte interface. 相似文献
15.
Li Chen Changzhou Yuan Bo Gao Shengyao Chen Xiaogang Zhang 《Journal of Solid State Electrochemistry》2009,13(12):1925-1933
An organic–inorganic poly(3,4-ethylenedioxythiophene) (PEDOT)/RuO2·xH2O nanocomposite (approximately 1 wt.% RuO2) has been successfully prepared for the first time under microwave irradiation within 5 min with power 900 W via in situ
chemical polymerization. The morphology and structure of the resultant material is characterized by transmission electron
microscope and Fourier transform infrared. Moreover, the electrochemical properties of the synthesized nanocomposite can be
controlled by adjusting the annealing temperature, which is definitely illustrated by cyclic voltammetry, galvanostatic charge–discharge,
and electrochemical impedance spectra. Electrochemical data have shown that the PEDOT/RuO2·xH2O nanocomposite annealed at 150 °C possesses the most favorable charge/discharge ability with a specific capacitance of 153.3 F
g−1 at a current density of 150 mA g−1 and the high efficient utilization of PEDOT at various current densities. Furthermore, such composite has a less capacitance
degradation of 23.8% after 1,000 continuous cycles. The improved electrochemical performance are mainly attributed to the
large electroactive surface of nanocomposite and the existence of amorphous RuO2·xH2O particles as well as a synergistic effect of the polymer PEDOT and annealed RuO2·xH2O. Thus, the PEDOT/RuO2·xH2O nanocomposite annealed at 150 °C can act as a promising electroactive material for supercapacitor application. 相似文献
16.
Silica gel was prepared by the sol–gel method, modified with nanometer-sized zirconium oxide, and this material was characterized
by X-ray diffraction. A micro-column packed with silica gel modified with nanometer zirconium oxide as sorbent has been developed
for the quantitative separation and preconcentration of trace amounts of chromium(III) prior to their determination by electrothermal
atomic absorption spectrometry. Total chromium was determined after the reduction of chromium(VI) to chromium(III) by 10%
(m/v) of aqueous ascorbic acid as reducing reagent. The adsorption capacity for chromium(III) was found to be 2.36 mg g−1. The detection limit for chromium(III) was 15 ng L−1 with an enrichment factor of 100. The relative standard deviation was 3.2% (n = 7, c = 2.0 ng mL−1). 相似文献
17.
通过静电纺丝法制备Mn4+掺杂的Co3O4复合纳米纤维,利用XRD、XPS、BET、SEM和电化学工作站等对材料的结构、成分、形貌和电化学性能进行表征与测试。研究发现,通过Mn4+掺杂,Co3O4复合纳米纤维的电化学性能得到明显改善。当nCo∶nMn=20∶2时,相应的复合纤维具有较大比表面积68 m2·g-1,而且该样品呈现出清晰的氧化还原峰,在1 A·g-1的电流密度下,放电比电容量为585 F·g-1,这比纯Co3O4纳米纤维的416 F·g-1,有显著提高;循环500圈电容保持率达到82.6%,而纯Co3O4纳米纤维则是76.4%。 相似文献
18.
Conducting polymer poly(pyrrole) (PPy) doped with Nafion was successfully used as ion-to-electron transducer in the construction
of a solid-contact Pb2+-selective polymeric membrane electrode. The Nafion dopant can effectively increase the capacitance of the conducting polymer
and improve the mechanical robustness of the coating. The transducer layer, PPy-Nafion, characterized by cyclic voltammetry
and electrochemical impedance spectroscopy, exhibits a sufficiently high bulk (redox) capacitance and fast ion and electron
transport process. The new Pb2+-selective polymeric membrane electrode, based on PPy-Nafion film as solid contact, shows stable Nernstian characteristics
in Pb(NO3)2 solution within the concentration range of 1.0 × 10−7–1.0 × 10−3 M, and the detection limit is 4.3 × 10−8 M. The potential stability of the electrode and the influence of the interfacial water layer were also evaluated by chronopotentiometry
and potentiometric water layer test, respectively. The results show that the solid-contact Pb2+-selective electrode, based on PPy-Nafion film as ion-to-electron transducer, can effectively overcome the potential drift
and reduce the water layer between the PPy-Nafion transducer layer and the ion-selective membrane. 相似文献
19.
Jixia Song Junhua Yuan Fei Li Dongxue Han Jiangfeng Song Li Niu 《Journal of Solid State Electrochemistry》2010,14(10):1915-1922
Oxygen electrochemical reduction on gold–polyaniline (Au–PANI) porous nanocomposite-modified glassy carbon electrode in basic
media was described. The as-prepared Au–PANI porous nanocomposite showed superior tunable activity for electrochemical reduction
of oxygen. The specific surface area of Au–PANI porous nanocomposites was evaluated to be about 11.3 m2 g−1 through a convenient voltammetric approach. Rotating ring-disk electrode experiments further demonstrated the number of electrons
exchanged in oxygen reduction increased from 2e to 4e with increasing the trigger potential from 300, to 500, 700 mV. The
tunable activity in electrochemical reduction of oxygen was achieved as a result of positive potential-induced formation and
reduction of Au surface oxide. However, the tunable oxygen reduction reaction is fit for applying potential in a linear positive-going
potential sweep. Irreversible ORR tunability was found after a more active surface formed at 700 mV. To optimize the applied
potential window on these Au-based porous materials has potential applications such as in electrochemical sensing, fuel cells,
or getting rid of the interference from the coexisted substances. 相似文献
20.
A. C. Tavares M. A. M. Cartaxo M.I. da Silva Pereira F. M. Costa 《Journal of Solid State Electrochemistry》2001,5(1):57-67
Studies on the electrochemical behaviour of Ni1−
x
Cu
x
Co2O4 (x ≤ 0.75) and NiCo2−
y
Cu
y
O4 (y ≤ 0.30) electrodes in 5 mol dm−3 KOH aqueous solutions are presented. The oxide layers have been prepared by thermal decomposition of aqueous nitrate solutions
on nickel supports at 623 K. Powder samples were also prepared by thermal decomposition under the same conditions. The powder
samples and the oxide layers were characterised by X-ray powder diffraction. The influence of the copper content on the voltammetric
response of the electrodes and activity towards oxygen evolution reaction is analysed and correlated with the surface composition
of the electrodes by means of X-ray photoelectron spectroscopy data. The analysis of the results reveals that the presence
of Cu affects the electrode behaviour and its influence depends on which cation has been replaced.
Received: 22 February 1999 / Accepted: 26 October 1999 相似文献