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1.
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
2.
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
3.
Nano-structured spinel Li2Mn4O9 powder was prepared via a combustion method with hydrated lithium acetate (LiAc·2H2O), manganese acetate (MnAc2·4H2O), and oxalic acid (C2H2O4·2H2O) as raw materials, followed by calcination of the precursor at 300 °C. The sample was characterized by X-ray diffraction,
scanning electron microscope, and energy-dispersive X-ray spectroscopy techniques. Electrochemical performance of the nano-Li2Mn4O9 material was studied using cyclic voltammetry, ac impedance, and galvanostatic charge/discharge methods in 2 mol L−1 LiNO3 aqueous electrolyte. The results indicated that the nano-Li2Mn4O9 material exhibited excellent electrochemical performance in terms of specific capacity, cycle life, and charge/discharge
stability, as evidenced by the charge/discharge results. For example, specific capacitance of the single Li2Mn4O9 electrode reached 407 F g−1 at the scan rates of 5 mV s−1. The capacitor, which is composed of activated carbon negative electrode and Li2Mn4O9 positive electrode, also exhibits an excellent cycling performance in potential range of 0–1.6 V and keeps over 98% of the
maximum capacitance even after 4,000 cycles. 相似文献
4.
Xin Zhang Suqin Liu Kelong Huang Shuxin Zhuang Jun Guo Tao Wu Ping Cheng 《Journal of Solid State Electrochemistry》2012,16(3):937-944
The macroporous Li3V2(PO4)3/C composite was synthesized by oxalic acid-assisted carbon thermal reaction, and the common Li3V2(PO4)3/C composite was also prepared for comparison. These samples were characterized by X-ray diffraction (XRD), scanning electron
microscope (SEM), and electrochemical performance tests. Based on XRD and SEM results, the sample has monoclinic structure
and macroporous morphology when oxalic acid is introduced. Electrochemical tests show that the macroporous Li3V2(PO4)3/C sample has a high initial discharge capacity (130 mAh g−1 at 0.1 C) and a reversible discharge capacity of 124.9 mAh g−1 over 20 cycles. Moreover, the discharge capacity of the sample is still 91.5 mAh g−1, even at a high rate of 2 C, which is better than that of the sample with common morphology. The improvement in electrochemical
performance should be attributed to its improved lithium ion diffusion coefficient for the macroporous morphology, which was
verfied by cyclic voltammetry and electrochemical impedance spectroscopy. 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.
Jing-Jing Deng Jian-Cheng Deng Zi-Ling Liu Hui-Ren Deng Bo Liu 《Journal of Solid State Electrochemistry》2009,13(9):1387-1394
Ni–Co oxide nanocomposite was prepared by thermal decomposition of the precursor obtained via a new method—coordination homogeneous
coprecipitation method. The synthesized sample was characterized physically by X-ray diffraction, scanning electron microcopy,
energy dispersive spectrum, transmission electron microscope, and Brunauer–Emmett–Teller surface area measurement, respectively.
Electrochemical characterization of Ni–Co oxide electrode was examined by cyclic voltammetry, galvanostatic charge–discharge,
and electrochemical impedance measurements in 6-mol L−1 KOH aqueous solution electrolyte. The results indicated that the addition of cobalt oxide not only changed the morphology
of NiO but also enhance its electrochemical capacitance value. A specific capacitance value of 306 F g−1 of Ni–Co oxide nanocomposite with n
Co = 0.5 (n
Co is the mole fraction of Co with respect to the sum of Co and Ni) was measured at the current density of 0.2 A g−1, nearly 1.5 times greater than that of pure NiO electrode. Lower resistance and better rate capability can also be observed. 相似文献
7.
Among the various positive electrode materials investigated for Li-ion batteries, spinel LiMn2O4 is one of the most important materials. Small particles of the active materials facilitate high-rate capability due to large
surface to mass ratio and small diffusion path length. The present work involves the synthesis of submicron size particles
of LiMn2O4 in a quaternary microemulsion medium. The precursor obtained from the reaction is heated at different temperatures in the
range from 400 to 900 °C. The samples heated at 800 and 900 °C are found to possess pure spinel phase with particle size <200 nm,
as evidenced from XRD, SEM, and TEM studies. The electrochemical characterization studies provide discharge capacity values
of about 100 mAh g−1 at C/5 rate, and there is a moderate decrease in capacity by increasing the rate of charge–discharge cycling. Studies also
include charge–discharge cycling and ac impedance studies in temperature range from −10 to 40 °C. Impedance data are analyzed
with the help of an equivalent circuit and a nonlinear least squares fitting program. From temperature dependence of charge-transfer
resistance, a value of 0.62 eV is obtained for the activation energy of Mn3+/Mn4+ redox process, which accompanies the intercalation/deintercalation of the Li+ ion in LiMn2O4. 相似文献
8.
R. Sathiyamoorthi P. Santhosh P. Shakkthivel T. Vasudevan 《Journal of Solid State Electrochemistry》2007,11(12):1665-1669
Layered Ti-doped lithiated nickel cobaltate, LiNi0.8Co0.2 − xTixO2 (where x = 0.01, 0.03, and 0.05) nanopowders were prepared by wet-chemistry technique. The structural properties of synthesized materials
were characterized by X-ray diffraction (XRD) and thermo-gravimetric/differential thermal analysis (TG/DTA). The morphological
changes brought about by the changes in composition of LiNi0.8Co0.2 − xTixO2 particles were examined through surface examination techniques such as scanning electron microscopy (SEM) and transmission
electron microscopy (TEM) analyses. Electrochemical studies were carried out using 2016-type coin cell in the voltage range
of 3.0–4.5 V (vs carbon) using 1 M LiClO4 in ethylene carbonate and diethyl carbonate as the electrolyte. Among the various concentrations of Ti-doped lithiated nickel
cobaltate materials, C/LiNi0.8Co0.17Ti0.03O2 cell gives stable charge–discharge features. 相似文献
9.
Junqing Dou Xueya Kang Tuerdi Wumaier Hongwei Yu Ning Hua Ying Han Guoqing Xu 《Journal of Solid State Electrochemistry》2012,16(4):1481-1486
The effect of the lithium boron oxide glass coating on the electrochemical performance of LiNi1/3Co1/3Mn1/3O2 has been investigated via solution method. The morphology, structure, and electrochemical properties of the bare and coated
LiNi1/3Co1/3Mn1/3O2 are characterized by scanning electron microscopy, X-ray diffraction, electrochemical impedance spectroscopy, and charge–discharge
tests. The results showed that the lattice structure of LiNi1/3Co1/3Mn1/3O2 is not changed after coating. The coating sample shows good high-rate discharge performance (148 mAh g−1 at 5.0 C rate) and cycling stability even at high temperature (with the capacities retention about 99% and 87% at room and
elevated temperature after 50 cycles). The Li+ diffusion coefficient is also largely improved, while the charge transfer resistance, side reactions within cell, and the
erosion of Hydrofluoric Acid all reduced. Consequently, the good electrochemical performances are obtained. 相似文献
10.
D. M. Ortega-Sotelo J. G. Gonzalez-Rodriguez M. A. Neri-Flores M. Casales L. Martinez A. Martinez-Villafañe 《Journal of Solid State Electrochemistry》2011,15(9):1997-2004
The corrosion inhibition of X-70 pipeline steel in saltwater saturated with CO2 at 50 °C with carboxyamido imidazoline has been evaluated by using electrochemical techniques. Techniques included polarization
curves, linear polarization resistance, electrochemical impedance, and electrochemical noise measurements. Inhibitor concentrations
were 0, 1.6 × 10−5, 3.32 × 10−5, 8.1 × 10−5, 1.6 × 10−4, and 3.32 × 10−4 mol l−1. All techniques showed that the best corrosion inhibition was obtained by adding 8.1 × 10−5 mol l−1 of carboxyamido imidazoline. For inhibitor concentrations higher than 8.1 × 10−5 mol l−1 a desorption process occurs, and an explanation has been given for this phenomenon. 相似文献
11.
Zhao Yang Gao-Shao Cao Jian Xie Xin-Bing Zhao 《Journal of Solid State Electrochemistry》2012,16(3):1271-1277
LiMnPO4, with a particle size of 50–150 nm, was prepared by oleic acid-assisted solid-state reaction. The materials were characterized
by X-ray diffraction, field emission scanning electron microscopy, and transmission electron microscopy. The electrochemical
properties of the materials were investigated by galvanostatic cycling. It was found that the introduction of oleic acid in
the precursor led to smaller particle size and more homogeneous size distribution in the final products, resulting in improved
electrochemical performance. The electrochemical performance of the sample could be further enhanced by Co doping. The mechanism
for the improvement of the electrochemical performance was investigated by Li-ion chemical diffusion coefficient
( [(D)\tilde]\textLi ) \left( {{{\tilde{D}}_{\text{Li}}}} \right) and electrochemical impedance spectroscopy measurements. The results revealed that the
[(D)\tilde]\textLi {\tilde{D}_{\text{Li}}} values of LiMnPO4 measured by cyclic voltammetry method increase from 9.2 × 10−18 to 3.0 × 10−17 cm2 s−1 after Co doping, while the charge transfer resistance (R
ct) can be decreased by Co doping. 相似文献
12.
Yongli Cui Wenjing Bao Zheng Yuan Quanchao Zhuang Zhi Sun 《Journal of Solid State Electrochemistry》2012,16(4):1551-1559
A comparative study of submicro-crystalline spinel LiMn2O4 powders prepared by two different soft chemical routes such as hydrothermal and sol–gel methods is made. The dependence of
the physicochemical properties of the spinel LiMn2O4 powder has been extensively investigated by using X-ray diffraction, Fourier transform infrared spectroscopy, scanning electron
microscope, cyclic voltammogram, charge–discharge test, and electrochemical impedance spectroscopy (EIS). The results show
that the electrochemical performances of spinel LiMn2O4 depend strongly upon the synthesis method. The LiMn2O4 powder prepared by hydrothermal route has higher specific capacity and better cycling performance than the one synthesized
from sol–gel method. The former has the max discharge capacity of 114.36 and 99.78 mAh g−1 at the 100th cycle, while the latter has the max discharge capacity of 98.67 and 60.25 mAh g−1 at the 100th cycle. The selected equivalent circuit can fit well the EIS results of synthesized LiMn2O4. For spinel LiMn2O4 from sol–gel method and hydrothermal route in the first charge process R
SEI remain almost invariable, R
e and R
ct first decreasing and then increasing with the increase of polarization potential. 相似文献
13.
Huaibing Sun Yungui Chen Chenghao Xu Ding Zhu Lihong Huang 《Journal of Solid State Electrochemistry》2012,16(3):1247-1254
Spinel powders of LiMn2−x
RE
x
O4 (RE = La, Ce, Nd, Sm; 0 ≤ x ≤ 0.1) have been synthesized by solid-phase reaction. The structure and electrochemical properties of these electrode materials
were characterized by X-ray diffraction (XRD), cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS) and charge–discharge
experiment. The part substitution of rare-earth element RE for Mn in LiMn2O4 decreases the lattice parameter, resulting in the improvement of structural stability, and decreases the charge transfer
resistance during the electrochemical process of LiMn2O4. As a result, the cycle ability, 55 °C high-temperature and high-rate performances of LiMn2−x
RE
x
O4 electrode materials are significantly improved with increasing RE addition, compared to the pristine LiMn2O4. 相似文献
14.
M. Prabu S. Selvasekarapandian M. V. Reddy B. V. R. Chowdari 《Journal of Solid State Electrochemistry》2012,16(5):1833-1839
Olivine-structured LiCoPO4 is synthesized by a Pechini-type polymer precursor method. The structure and the morphology of the compounds are studied
by the Rietveld-refined X-ray diffraction, scanning electron microscopy, Brunauer, Emmett, and Teller surface area technique,
infrared spectroscopy, and Raman spectroscopy techniques, respectively. The ionic conductivity (σ ionic), dielectric, and electric modulus properties of LiCoPO4 are investigated on sintered pellets by impedance spectroscopy in the temperature range, 27–50 °C. The σ (ionic) values at 27 and 50 °C are 8.8 × 10−8 and 49 × 10−8 S cm−1, respectively with an energy of activation (E
a) = 0.43 eV. The electric modulus studies suggest the presence of non-Debye type of relaxation. Preliminary charge–discharge
cycling data are presented. 相似文献
15.
Dao-Lai Fang Bing-Cai Wu Yong Yan Ai-Qin Mao Cui-Hong Zheng 《Journal of Solid State Electrochemistry》2012,16(1):135-142
Mesoporous Mn–Ni oxides with the chemical compositions of Mn1-x
Ni
x
O
δ
(x = 0, 0.2, and 0.4) were prepared by a solid-state reaction route, using manganese sulfate, nickel chloride, and potassium
hydroxide as starting materials. The obtained Mn–Ni oxides, mainly consisting of the phases of α- and γ-MnO2, presented irregular mesoporous agglomerates built from ultra-fine particles. Specific surface area of Mn1–x
Ni
x
O
δ
was 42.8, 59.6, and 84.5 m2 g−1 for x = 0, 0.2, and 0.4, respectively. Electrochemical properties were investigated by cyclic voltammetry and galvanostatic charge/discharge
in 6 mol L−1 KOH electrolyte. Specific capacitances of Mn1-x
Ni
x
O
δ
were 343, 528, and 411 F g−1 at a scan rate of 2 mV s−1 for x = 0, 0.2, and 0.4, respectively, and decreased to 157, 183, and 130 F g−1 with increasing scan rate to 100 mV s−1, respectively. After 500 cycles at a current density of 1.24 A g−1, the symmetrical Mn1–x
Ni
x
O
δ
capacitors delivered specific capacitances of 160, 250, and 132 F g−1 for x = 0, 0.2, and 0.4, respectively, retaining about 82%, 89%, and 75% of their respective initial capacitances. The Mn0.8Ni0.2O
δ
material showed better supercapacitive performance, which was promising for supercapacitor applications. 相似文献
16.
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
17.
B. Das M. V. Reddy G. V. Subba Rao B. V. R. Chowdari 《Journal of Solid State Electrochemistry》2011,15(2):259-268
Nano-composites of SnO(V2O3)
x
(x = 0, 0.25, and 0.5) and SnO(VO)0.5 are prepared from SnO and V2O3/VO by high-energy ball milling (HEB) and are characterized by X-ray diffraction (XRD), scanning electron microscopy, and
high-resolution transmission electron microscopy techniques. Interestingly, SnO and SnO(VO)0.5 are unstable to HEB and disproportionate to Sn and SnO2, whereas HEB of SnO(V2O3)
x
gives rise to SnO2.VO
x
. Galvanostatic cycling of the phases is carried out at 60 mA g−1 (0.12 C) in the voltage range 0.005–0.8 V vs. Li. The nano-SnO(V2O3)0.5 showed a first-charge capacity of 435 (±5) mAh g−1 which stabilized to 380 (±5) mAh g−1 with no noticeable fading in the range of 10–60 cycles. Under similar cycling conditions, nano-SnO (x = 0), nano-SnO(V2O3)0.25, and nano-SnO(VO)0.5 showed initial reversible capacities between 630 and 390 (±5) mAh g−1. Between 10 and 50 cycles, nano-SnO showed a capacity fade as high as 59%, whereas the above two VO
x
-containing composites showed capacity fade ranging from 10% to 28%. In all the nano-composites, the average discharge potential
is 0.2–0.3 V and average charge potential is 0.5–0.6 V vs. Li, and the coulombic efficiency is 96–98% after 10 cycles. The
observed galvanostatic cycling, cyclic voltammetry, and ex situ XRD data are interpreted in terms of the alloying–de-alloying
reaction of Sn in the nano-composite “Sn-VO
x
-Li2O” with VO
x
acting as an electronically conducting matrix. 相似文献
18.
J. Dailly F. Mauvy M. Marrony M. Pouchard Jean-Claude Grenier 《Journal of Solid State Electrochemistry》2011,15(2):245-251
Three selected materials have been prepared and shaped as cathode of half cells using the proton-conducting electrolyte BaCe0.9Y0.1O3 − δ
(BCY10): two perovskite compounds, Ba0.5Sr0.5Co0.8Fe0.2O3 − δ
(BSCF) and La0.6Sr0.4Fe0.8Co0.2O3 − δ
(LSFC), and the praseodymium nickelate Pr2NiO4 + δ
(PRN) having the K2NiF4-type structure. The electrochemical properties of these compounds have been studied under zero current conditions (two-electrode
cell) and under polarization (three-electrode cell). Their measured area-specific resistances were about 1–2 Ω cm2 at 600 °C. Under direct current polarization, it appears that the three compounds show almost similar values of current densities
at 625 °C; however, at lower temperatures, BSCF appears to be the most efficient cathode material. 相似文献
19.
Dan-Dan Zhao Zhi Yang Eric Siu-Wai Kong Cai-Ling Xu Ya-Fei Zhang 《Journal of Solid State Electrochemistry》2011,15(6):1235-1242
Manganese oxide (MnOx) has been coated on carbon nanotubes (CNTs) and fabricated as the electrodes for electrochemical capacitors (ECs) by cathodic
electrodeposition. In the process, randomly oriented CNT arrays are grown directly onto the Ti/Si substrates by chemical vapor
deposition method. Potentiostatic method has been utilized for cathodic electrodeposition of MnOx onto the surface of CNTs while immersed in KMnO4 solution. The highly porosity and fibrous microstructure of the as-prepared MnOx/CNT electrode is beneficial for the electrolyte access to the active material, whereas CNTs provide improved electronic conductivity.
Electrochemical investigations show that the increase in the loading mass of MnOx results in a significant reduction in the specific capacitances (SCs) of the MnOx/CNT electrodes. The MnOx/CNT electrode with MnOx loading mass of 50 μg shows a high SC of 400 F g−1 with good long cycle stability at a current density of 10 A g−1, suggesting its potential application in ECs. 相似文献
20.
Magnetic Co3O4 nanoparticles were prepared by using microporous regenerated cellulose films as sacrificial scaffolds. The cellulose macromolecules
and the porous structure of the films made them used as spatially confined reacting sites where Co(OH)2 nanoparticles could be synthesized in situ. When the cellulose matrix was removed by sintering at 500 °C, Co3O4 nanoparticles were obtained. XRD and XPS indicated that the prepared nanoparticles were pure Co3O4 without any impurity. TEM and SEM images revealed that the particle size of the nanoparticles was smaller than 100 nm. The
nanoparticles had weak ferromagnetic properties at 25 °C. Furthermore, the pronounced quantum confinement effects of the synthesized
nanoparticles have been observed, the optical bandgap energies determined were about 1.92 ~ 2.12 and 2.74 ~ 2.76 eV for O2− → Co3+ and O2− → Co2+ charge-transfer processes, respectively. Furthermore, the resulted Co3O4 nanoparticles behaved stable electrochemical performance with promising applications in the electrode for lithium ion battery. 相似文献