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1.
Compound Zn2SnO4 was synthesized by a hydrothermal method in which SnCl4 · 5H2O, ZnCl2 and N2H4 · H2O were used as reactants. Composite Zn2SnO4/C was then synthesized through a carbothermic reduction process using the as-prepared Zn2SnO4 and glucose as reactants. Comparing to the pure Zn2SnO4, some improved electrochemical properties were obtained for composite Zn2SnO4/C. When doped with 15% glucose, the composite Zn2SnO4/C showed the best electrochemical performance. Its first discharge capacity was about 1500 mA h g−1, with a capacity retain of 500 mA h g−1 in the 40th cycle at a constant current density of 100 mA/g in the voltage range of 0.05–3.0 V. There were also some differences
displayed in their cyclic voltammogram. 相似文献
2.
Lu Lu Xiaofu Sun Jun Ma Qinggong Zhu Congyi Wu Dexin Yang Buxing Han 《中国科学:化学(英文版)》2018,61(2):228-235
Electrocatalytic reduction of CO2 is a promising route for energy storage and utilization. Herein we synthesized SnO2 nanosheets and supported them on N-doped porous carbon (N-PC) by electrodeposition for the first time. The SnO2 and N-PC in the SnO2@N-PC composites had exellent synergistic effect for electrocatalytic reduction of CO2 to HCOOH. The Faradaic efficiency of HCOOH could be as high as 94.1% with a current density of 28.4 mA cm?2 in ionic liquid-MeCN system. The reaction mechanism was proposed on the basis of some control experiments. This work opens a new way to prepare composite electrode for electrochemical reduction of CO2. 相似文献
3.
A PbO2-SnO2 composite anode with interconnected structure is prepared for organics electro-incineration through a two-step method, thermal-decomposition
process and subsequent low-current density electrodeposition process. The element mapping, together with the impedance spectra
of the composite electrode, confirms that an interconnected architecture of SnO2 and PbO2 grains, instead of a lamellar structure, was obtained on the Ti substrate. A lower electrodeposition current density (≤10
mA cm−2) is very crucial for the formation of a porous surface and an interconnected architecture of two oxides inside. The asprepared
electrode exhibits an enhanced electrocatalytic activity on the mineralization of phenol and a long service life due to the
interconnected architecture, which helps to utilize the merits of these two metal oxides simultaneously. This two-step method
also provides us a novel and facile way to fabricate a series of composite material such as oxide-oxide, oxide-metal composite
electrodes. 相似文献
4.
Electrocatalytic oxygen reduction was studied on a RuxFeySez(CO)n cluster catalyst with Vulcan carbon powder dispersed into a Nafion film coated on a glassy carbon electrode. The synthesis
of the electrocatalyst as a mixture of crystallites and amorphous nanoparticles was carried out by refluxing the transition
metal carbonyl compounds in an organic solvent. Electrocatalysis by the cluster compound is discussed, based on the results
of rotating disc electrode measurements in a 0.5 M H2SO4. A Tafel slope of −80.00±4.72 mV dec−1 and an exchange current density of 1.1±0.17×10−6 mA cm−2 was calculated from the mass transfer-corrected curve. It was found that the electrochemical reduction reaction follows the
kinetics of a multielectronic (n=4e−) charge transfer process producing water, i.e. O2+4H++4e−→2H2O.
Electronic Publication 相似文献
5.
The poly(o-anisidine)–sulfuric acid–glucose oxidase (POA–H2SO4–GOx) electrode has been investigated in the present work. Platinum electrode was used for the synthesis of poly (o-anisidine)–sulfuric acid (POA–H2SO4) film using galvanostatic method with 0.2 M o-anisidine, 1.0 M H2SO4 solution, 1.0 pH and 2 mA/cm2 applied current density. The synthesized film was characterized using electrochemical technique, conductivity measurement,
UV–visible spectroscopy, Fourier transform infrared spectroscopy, and scanning electron microscopy. GOX was immobilized on synthesized POA–H2SO4 film by cross-linking via glutaraldehyde in phosphate and acetate buffer. The Michaelis–Menten constant (
K\textm¢K_{\text{m}}^\prime ) was determined for the immobilized enzyme. The glucose oxidase electrode shows the maximum current response at pH 5.5 and
potential 0.6 V. The sensitivity of POA–H2SO4–GOX electrode in phosphate and acetate buffer has been recorded. The results of this study reveal that the phosphate buffer gives
fast response as compared to acetate buffer in amperometric measurements. 相似文献
6.
Electroless and electroplated nickel electrodes are extensively used for hydrogen evolution reaction (HER). In the present
work, TiO2-supported IrO2 mixed oxide composite was prepared and used to reinforce Ni–P electroless plates to be used as catalytic electrodes for HER.
The electrodes exhibited high electrocatalytic activity when the electrodes were used for HER. All the parameters including
particle size of the catalyst, surface roughness, and surface active sites were studied. The particle size of the IrO2 catalyst in the mixed oxide was found to have high influence on the catalytic activity of the electrodes. Low overpotential
as low as 70 mV at a current density of 200 mA cm−2 was achieved with the mixed oxide-reinforced Ni–P electrodes. 相似文献
7.
The electrolyses of solutions of bismuth oxide and tellurium oxide in nitric acid with molar ratios of Bi:Te=3:3–4:3 lead
to cathodic deposits of films of bismuth telluride (Bi2Te3), an n-type semiconductor. Current densities of 2–5 mA/cm2 were applied. Voltammetric investigations showed that Bi2Te3 deposition occurred at potentials more negative than −0.125 V (Ag/AgCl, 3 M KCl). The deposit was identified as bismuth telluride
(γ-phase) by X-ray analysis. Hall-effect measurements verified the n-type semiconducting behaviour. The films can be deposited
in microstructures for thermoelectric microdevices like thermoelectric batteries or thermoelectric sensors. 相似文献
8.
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
9.
Aneta Kolary-Zurowska Agata Zieleniak Krzysztof Miecznikowski Beata Baranowska Adam Lewera Sebastian Fiechter Peter Bogdanoff Iris Dorbandt Roberto Marassi Pawel J. Kulesza 《Journal of Solid State Electrochemistry》2007,11(7):915-921
An electrocatalytic system that utilizes tungsten oxide modified carbon-supported RuSex nanoparticles is developed and characterized here using transmission electron microscopy and such electrochemical diagnostic
techniques as cyclic voltammetry and rotating ring-disk voltammetry, as well as upon its introduction (as cathode) to the
low-temperature hydrogen–oxygen fuel cell. After the modification of RuSex catalytic centers with ultra-thin films of WO3, the potential of oxygen reduction in 0.5 mol dm−3 H2SO4 (in the absence and presence of methanol) is shifted ca. 70 mV (under rotating disk voltammetric conditions) towards more
positive values, and the percent formation (at ring) of the undesirable hydrogen peroxide has decreased approximately twice
when compared to the WO3-free system. Relative to bare electrocatalyst, an increase of power density from 75 to 100 mW cm−2 (at 300 mA cm−2) has been observed upon utilization of WO3-modified RuSex in polymer electrolyte membrane fuel cell at 80 °C. In comparison to Vulcan-supported Pt nanoparticles, the overall electrocatalytic
performance of tungsten oxide modified carbon-supported RuSex nanoparticles is lower, but the latter system is practically insensitive to the presence of methanol even at 0.5 mol dm−3 level.
Dedicated to Professor Dr. Algirdas Vaskelis on the occassion of his 70th birthday. 相似文献
10.
Alkaline–Acid Zn–H2O Fuel Cell for the Simultaneous Generation of Hydrogen and Electricity
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Pingwei Cai Yan Li Genxiang Wang Prof. Dr. Zhenhai Wen 《Angewandte Chemie (International ed. in English)》2018,57(15):3910-3915
An alkaline–acid Zn–H2O fuel cell is proposed for the simultaneous generation of electricity with an open circuit voltage of about 1.25 V and production of H2 with almost 100 % Faradic efficiency. We demonstrate that, as a result of harvesting energy from both electrochemical neutralization and electrochemical Zn oxidation, the as‐developed hybrid cell can deliver a power density of up to 80 mW cm?2 and an energy density of 934 Wh kg?1 and maintain long‐term stability for H2 production with an output voltage of 1.16 V at a current density of 10 mA cm?2. 相似文献
11.
Gennady I. Ostapenko 《Journal of Solid State Electrochemistry》2002,6(2):139-141
The electrochemical behaviour of the Ag(Hg)/Ag4RbI5 interface is investigated by a potentiostatic pulse method. It is found that the rate-determining step of the electrode reaction
is electron transfer with an exchange current density of 68 mA cm–2 and a transfer coefficient of approximately 0.45. The order of the electrochemical reaction for silver oxidation is estimated
from polarization investigations of silver amalgam in various concentrations. From this it is deduced that the mercury is
ionized and is implanted in the electrolyte together with silver under anodic polarization: 15Ag+85Hg–100e–→15Ag++85Hg+. From comparison of the electrochemical behaviour of the Ag(Hg)/Ag4RbI5 and Ag/Ag4RbI5 interfaces it is concluded that the rate of anodic silver dissolution on the Ag/Ag4RbI5 interface is limited by crystallization effects.
Electronic Publication 相似文献
12.
Daixin Ye Yanhong Xu Liqiang Luo Yaping Ding Yulong Wang Xiaojuan Liu 《Journal of Solid State Electrochemistry》2012,16(4):1635-1642
A novel electrochemical sensor based on LaNi0.5Ti0.5O3/CoFe2O4 nanoparticle-modified electrode (LNT–CFO/GCE) for sensitive determination of paracetamol (PAR) was presented. Experimental
conditions such as the concentration of LNT–CFO, pH value, and applied potential were investigated. Under the optimum conditions,
the electrochemical performances of LNT–CFO/GCE have been researched on the oxidation of PAR. The electrochemical behaviors
of PAR on LNT–CFO/GCE were investigated by cyclic voltammetry. The results showed that LNT–CFO/GCE exhibited excellent promotion
to the oxidation of PAR. The over-potential of PAR decreased significantly on the modified electrode compared with that on
bare GCE. Furthermore, the sensor exhibits good reproducibility, stability, and selectivity in PAR determination. Linear response
was obtained in the range of 0.5 to 901 μM with a detection limit of 0.19 μM for PAR. 相似文献
13.
Shenghui Zhang 《Russian Journal of Electrochemistry》2011,47(11):1257-1261
A mesoporous TiO2 (meso-TiO2) was synthesized, and used to prepare modified carbon paste electrode (CPE). The electrochemical sensing properties were
characterized using K3[Fe(CN)6], showing that meso-TiO2 modified CPE possesses larger surface area and higher electron transfer rate. The electrochemical behavior of p-cresol was investigated. At the meso-TiO2 modified CPE, the oxidation peak current of p-cresol remarkably increases, and the oxidation peak potential shifts negatively, suggesting that meso- TiO2 exhibits highly efficient catalytic activity to the oxidation of p-cresol. Based on this, a sensitive, rapid and convenient electrochemical method was developed for the detection of p-cresol. The linear range is from 1.5 × 10−7 and 2.0 × 10−5 mol l−1, and the limit of detection is as low as 8.0 × 10−8 mol l−1. Finally, the new method was successfully used to determine p-cresol in water samples. 相似文献
14.
Ce-substituted BiFeO3 film (BCFO film) have been prepared by sol–gel process on F doped SnO2 (FTO)/glass substrates. The effects of Ce substitution on the structural and electrical properties have been reported. X-ray
diffraction data confirmed the R3c structure with the elimination of all secondary phases. We observed an increase in the
remnant polarization (Pr) with Ce substitution and obtained a maximum value of ∼84 μC/cm2 in 5% Ce-substituted film. The dielectric constant of the films was increased from 280 to about 420 for the BiFeO3 film and 5% Ce-substituted BCFO film, respectively and the films showed excellent dielectric loss behavior. Moreover, the
leakage current was substantially reduced by the Ce substitution. 相似文献
15.
Single-phase LiCoPO4 nanoparticles were synthesized by solid-state reaction method and subsequent high-energy ball milling. The electrochemical
properties of LiCoPO4/Li batteries were analyzed by ac impedance experiments, cyclic voltammetry (CV), and charge/discharge tests. The structural
and morphological performance of LiCoPO4 nanoparticles was investigated by X-ray diffraction (XRD), scanning electron microscope (SEM), and transmission electron
microscope (TEM). The XRD result demonstrated that LiCoPO4 nanoparticles had an orthorhombic olivine-type structure with a space group of Pmnb. Different conductive additives including
acetylene black and carbon black (SP270) were used to fabricate electrodes. The morphologies of the electrodes and different
conductive additives were observed by field emission-scanning electron microscopy (FE-SEM). LiCoPO4/Li battery with acetylene black showed the best electrochemical properties, and exhibited a discharge plateau at around 4.7 V
with an initial discharge capacity of 110 mAh g−1 at a discharge current density of 0.05 mA cm−2 at 25 °C. 相似文献
16.
Ben Hui Wang Ji De Wang RuiQuan Liu Ya Hong Xie Zhi Jie Li 《Journal of Solid State Electrochemistry》2007,11(1):27-31
A new type of oxide–salt composite electrolyte, yttrium doped ceria YDC–Ca3(PO4)2–K3PO4, was developed and demonstrated for its promising use for ammonia synthesis. Using this composite electrolyte, ammonia was
synthesized from nitrogen and natural gas at atmospheric pressure in the solid-state proton conducting cell reactor, and the
optimal condition for ammonia production was determined . The evolved rate of ammonia is up to 6.95×10−9 mol s−1 cm−2. 相似文献
17.
Jinyi Chen Guangzhong Yang Wanyi Li Jiashou Sun 《Russian Journal of Electrochemistry》2009,45(8):908-912
The virgin activated carbon (AC) was oxidized by 30% H2O2 under the ultrasonic condition for 6 h (denoted as AC-6). The electrochemical response of Pb2+ at the AC-6 modified paste electrode was investigated, suggesting that AC-6 shows much higher accumulation efficiency to
trace levels of Pb2+. Based on this, a sensitive and convenient electrochemical method was developed for the determination of Pb2+ utilizing the excellent properties of AC-6. In pH 3.6 HAc-NaAc buffer, Pb2+ was easily accumulate at the surface of AC-6 modified paste electrode, then reduced to Pb at −1.20 V. During the following
anodic sweep, the reduced Pb was oxidized and resulted in an oxidation stripping peak at −0.58 V. The stripping peak current
is proportional to the concentration of Pb2+ over the range from the 8.0 × 10−9 to 2.0 × 10−6 mol l−1, and the limit of detection is as low as 2.0 × 10−9 mol l−1. Finally, this newly-developed method was successfully employed to determine Pb2+ in water samples. 相似文献
18.
Mohan M. Rao C. Liebenow M. Jayalakshmi H. Wulff U. Guth F. Scholz 《Journal of Solid State Electrochemistry》2001,5(5):348-354
Lithium nickelate (Li0.88Ni1.12O2), lithium cobaltate (LiCoO2) and lithium manganate (LiMn2O4) were synthesized by fast self-propagating high-temperature combustion and their phase purity and composition were characterized
by X-ray diffraction and inductively coupled plasma spectroscopy. The electrochemical behaviour of these oxides was investigated
with regard to potential use as cathode materials in lithium-ion secondary batteries. The cyclic voltammograms of these cathode
materials recorded in 1 M LiClO4 in propylene carbonate at scan rates of 0.1 and 0.01 mV s–1 showed a single set of redox peaks. Charge-discharge capacities of these materials were calculated from the cyclic voltammograms
at different scan rates. The highest discharge capacity was observed in the case of Li0.88Ni1.12O2. In all the cases, at a very slow scan rate (0.01 mV s–1) the capacity of the charging (oxidation) process was higher than the discharging (reduction) process. A strong influence
of current density on the charge-discharge capacity was observed during galvanostatic cycling of Li0.88Ni1.12O2 and LiMn2O4 cathode materials. LiMn2O4 can be used as cathode material even at higher current densities (1.0 mA cm–2), whereas in the case of Li0.88Ni1.12O2 a useful capacity was found only at lower current density (0.2 mA cm–2). For the fast estimation of the cycling behaviour of LiMn2O4, a screening method was used employing a simple technique for immobilizing microparticles on an electrode surface.
Electronic Publication 相似文献
19.
J. Sharath Kumar Saikat Bolar Naresh Chandra Murmu R. Sankar Ganesh Hiroshi Inokawa Amit Banerjee Tapas Kuila 《Electroanalysis》2019,31(11):2120-2129
A core‐shell structure with CuO core and carbon quantum dots (CQDs) and carbon hollow nanospheres (CHNS) shell was prepared through facile in‐situ hydrothermal process. The composite was used for non‐enzymatic hydrogen peroxide sensing and electrochemical overall water splitting. The core‐shell structure was established from the transmission electron microscopy image analysis. Raman and UV‐Vis spectroscopy analysis confirmed the interaction between CuO and CQDs. The electrochemical studies showed the limit of detection and sensitivity of the prepared composite as 2.4 nM and 56.72 μA μM?1 cm?2, respectively. The core‐shell structure facilitated better charge transportation which in turn exhibited elevated electro‐catalysis towards hydrogen evolution reaction (HER), oxygen evolution reaction (OER) and overall water splitting. The overpotential of 159 mV was required to achieve 10 mA cm?2 current density for HER and an overpotential of 322 mV was required to achieve 10 mA cm?2 current density for OER in 1.0 M KOH. A two‐electrode system was constructed for overall water splitting reaction, which showed 10 and 50 mA cm?2 current density at 1.83 and 1.96 V, respectively. The prepared CuO@CQDs@CHNS catalyst demonstrated excellent robustness in HER and OER catalyzing condition along with overall water splitting reaction. Therefore, the CuO@CQDs@CHNS could be considered as promising electro‐catalyst for H2O2 sensing, HER, OER and overall water splitting. 相似文献
20.
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