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1.
The electrochemical behaviour of Co3O4 layers deposited by thermal decomposition of Co(NO3)2 at 200–500°C on titanium supports with and without an interlayer of RuO2 has been studied by cyclic voltammetry, chronopotentiometry and potential step experiments in alkaline solutions. Such variables as the calcination temperature, the solution pH, the potential sweep rate and the oxide loading have been investigated in detail to determine their influence on voltammetric peaks and voltammetric charge. Insight has been gained into the relevance of the latter to surface area determination and to proton diffusion into the oxide layer. The role of the support-active layer interface and especially that of the RuO2 interlayer has been scrutinized. The importance of surface studies for the understanding of the electrocatalytic behaviour of Co3O4 electrodes has been analysed.Presented at the 37th Meeting of the International Society of Electrochemistry, Vilnius, USSR, 25–29 August 1986. 相似文献
2.
以六水合硝酸钴(Co(NO3)2?6H2O)、苯甲酰丙酮(C10H10O2)为原料, 利用微波法合成了前体。前体在500℃空气条件下锻烧得到无定形Co3O4花球。通过 XRD、 SEM、TEM对目标产物进行了表征 , 研究了无定形Co3O4花球的微观结构、表面形貌。电化学测试结果表明,无定形Co3O4花球负极材料 在100mA/g的电流密度下,首次充电比容量达到826mAh/g;循环100圈后,容量保持率为89.2%,具有高的比容量、良好的循环性能和广泛的应用前景。 相似文献
3.
Junhua JiangAnthony Kucernak 《Electrochimica acta》2002,47(15):2381-2386
A novel class of electrochemical supercapacitor electrode material has been electrochemically synthesized from a manganese halide complex in water-containing acetonitrile electrolyte at room temperature. This material has been physically and chemically characterized by scanning electron microscopy, X-ray photoelectron microscopy (XPS), FT-Raman microscopy and cyclic voltammetry. XPS and FT-Raman characterization suggest that this material is composed of manganese oxide with a chemical composition of Mn3O4 and containing a moderate amount of carbon. Cyclic voltammetric characterization indicates that this material has higher electronic conductivity than usually seen for manganese oxide and that it shows fast kinetics for the charge-discharge process in both aqueous and acetonitrile electrolytes. The material provides a large pseudocapacitance over a potential window of about 1 V in aqueous electrolyte and about 2 V in acetonitrile electrolyte. It is therefore a good candidate as a material for an electrochemical supercapacitor electrode. 相似文献
4.
Journal of Porous Materials - Co3O4 has been widely investigated as a promising candidate anode material for lithium-ion batteries. We report on the porous Co3O4 column synthesized via a simple... 相似文献
5.
《Ceramics International》2022,48(17):24609-24618
The aim of this study was to synthesize CuFe2O4 together with g-C3N4 and GNPs in various combinations on the surface of Ni foam for use as anode materials in supercapacitors. The fabricated electrodes were investigated by XRD, FTIR, XPS, BET, SEM and TEM for content and by CV, GCD and EIS analysis for electrochemistry. The characterization results showed that CuFe2O4 was successfully synthesized together with g-C3N4 and GNPs in a nanosponge-like geometry. The highest value of specific capacitance was found to be 989 mF/cm2 at 2 mA measurement in the triple combination. Moreover, the stability of this electrode was measured to be 70% after 1500 cycles at 16 mA, while the energy and power densities were calculated to be 27.8 mWh/cm2 and 300 mW/cm2, respectively. The EIS results show that the carbon-based component increased the Cs value by decreasing the charge transfer and diffusion resistances of the electrodes. Compared to its counterparts in the literature, its Cs value is quite high, but its stability is low, so it can be used in low-cycle applications. 相似文献
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7.
《Ceramics International》2017,43(2):2057-2062
A novel Ni@NiCo2O4 core/shells structure consisting of the Ni microspheres skeletons and nanosheet-like NiCo2O4 skins was designed and investigated as the electrochemical electrode for supercapacitor. Due to the unique architecture with Ni microspheres as the highly conductive cores improving the electrical conductivity of electrode and external nanosheet-like NiCo2O4 shells as the efficient electrochemical active materials facilitating the contact between the electrode and electrolyte, the as-prepared Ni@NiCo2O4 exhibited excellent electrochemical performance with high specific capacity of 597 F g−1 (1 A g−1) as well as remarkable capacitance retention of 96% (3000 cycles). These impressive results pave the way to design high-performance electrode materials for energy storage. 相似文献
8.
Izan Izwan Misnon Karnan Manickavasakam Norhayati Nordin Rajan Jose 《International Journal of Applied Ceramic Technology》2023,20(3):2030-2042
In this work, conducting polymer modification on metal oxide surfaces was targeted to improve the composite conductivity and stability for electrochemical energy storage applications. Polyhedral cobalt oxide (Co3O4) was prepared using a molten salt combustion method and coated with polyaniline (PANI). The composite (PANI-CoM) was characterized using XRD, TGA, FTIR, FESEM, TEM, and BET. From cyclic voltammetry analysis in 6 M KOH, PANI-CoM shows a high CS (985 F/g) compared to bare Co3O4 (278 F/g), indicating that PANI coating has improved pseudocapacitive charge storability of the electrode. The electrolyte diffusion on the internal active surfaces has increased from 11% to 31%, contributed by the reduction of internal resistance by 29%. Activated carbon and ordered mesoporous carbon (OMC) were used to manufacture two sets of asymmetrical supercapacitor devices, and PANI-CoM/OMC functioned the best performance with an ED of 22 Wh/kg at a PD of 400 W/kg. 相似文献
9.
《Ceramics International》2016,42(11):12928-12931
The results of investigations of magnetic properties of Co3O4 polycrystals in powder morphology with average crystallite size of 10 µm are presented. The temperature dependence of the magnetic susceptibility, measured in a wide temperature interval (1.5≤T≤400 K) using SQUID magnetometer, as well as electron spin resonance (ESR) spectra measured at X-band and Q-band frequency ranges have been studied. Antiferromagnetism with a Néel temperature TN at about 39 K was observed from the analysis of evolution of molar magnetic susceptibility and ESR intensity as a function of temperature. ESR parameters namely g-factor, intensity (IESR), g-value, and linewidth ΔH for powder Co3O4 have been obtained. Some deviations from the expected values of some magnetic properties were determined and discussed. 相似文献
10.
S. Vijayanand R. Kannan H. S. Potdar V. K. Pillai P. A. Joy 《Journal of Applied Electrochemistry》2013,43(10):995-1003
Porous aggregated nanorods of Co3O4 with a surface area of ~100 m2 g?1 synthesized without using any templates or surfactants give very high specific capacitance of ~780 F g?1 when used as electrode in a faradaic supercapacitor, with a cycle life of more than 1,000 cycles. Further, in Li-ion batteries when used as an anode, the Co3O4 nanorods achieved a capacity of 1155 mA h g?1 in the first cycle and upon further cycling it is stabilized at 820 mA h g?1 for more than 25 cycles. Detailed characterization indicated the stability of the material and the improved performance is attributed to the shorter Li-insertion/desertion pathways offered by the highly porous nanostructures. The environmentally benign and easily scalable method of synthesis of the porous Co3O4 nanorods coupled with the superior electrode characteristics in supercapacitors and Li-ion batteries provide efficient energy storage capabilities with promising applications. 相似文献
11.
K. Seevakan A. Manikandan P. Devendran A. Baykal T. Alagesan 《Ceramics International》2018,44(15):17735-17742
Nanorod shaped cobalt molybdate (CoMoO4) electro-catalysts synthesized by microwave combustion route using urea as the fuel. The formation of monoclinic nanocrystalline structure, metal-oxygen (M–O) and chemical bonding was confirmed by X-ray powder diffractometry (XRD), Fourier transform infrared (FT-IR) and Raman spectroscopy, respectively. Scanning electron microscope (SEM) associated with energy dispersive X-ray (EDX) and high-resolution transmission electron microscope (HR-TEM) were used to confirm the morphology, elemental composition and particle size of the samples, respectively. The optical and defects were confirmed by the UV–vis. absorption and photoluminescence (PL) spectroscopy at room temperature (RT). The room temperature magnetic behaviors of product were investigated by vibrating sample magnetometer (VSM). Surface binding energy and element confirmation were examined by X-ray Photoelectron spectroscopy (XPS). The electrochemical (EC) performance was studied by cyclic voltammetry (CV), galvanostatic charge-discharge analysis (GCD) and electrochemical impedance spectroscopy (EIS) analysis. The CV curve proved the existence of redox pairs and the supercapacitor nature exhibited by the EIS (Nyquist plots). The GCD studies provided the non-symmetrical discharge curves and the highest specific capacitance (Csp) of ~ 133?F/g were acquired at a constant discharge current density (1?mA/cm?2). The cyclic stability investigations revealed capacitance retention of about 100% after 1000 cycles, proposing the prospective usage of CoMoO4 in energy-storage devices. 相似文献
12.
Muhammad Naveed ur Rehman Tauseef Munawar Muhammad Shahid Nadeem Faisal Mukhtar Adnan Maqbool Muhammad Riaz Sumaira Manzoor Muhammad Naeem Ashiq Faisal Iqbal 《Ceramics International》2021,47(13):18497-18509
Metal oxide nanoparticles and their composites with conducting polymers, specifically Polyaniline (PANI) were utilized for fabricating nanoscale supercapacitor (SC) electrode materials. In the present study, we have synthesized pristine Pr2O3, NiO, Co3O4 nanoparticles, binary PANI-Pr2O3, PANI-NiO, PANI-Co3O4, ternary Pr2O3–NiO–Co3O4, and quaternary PANI-Pr2O3–NiO–Co3O4 spherical core-shell nanocomposite using co-precipitation and ultra-sonication methods. The grown samples were characterized with different analytical techniques. The XRD pattern revealed that the as-synthesized products were crystalline with Pr2O3 hexagonal phase, NiO cubic phase, and Co3O4 cubic phase in pure and nanocomposites. The Williamson-Hall, Scherrer, and size-strain plot methods were employed to study the crystalline development and contribution of micro-strain. FTIR pattern exhibited the metal-oxygen and PANI bond vibrations. FE-SEM images shown the spherical core-shell shape morphology of quaternary nanocomposite. EDX evident the presence of praseodymium, cobalt, and nickel in synthesized samples. UV–vis spectroscopy confirmed the absorption in the visible region. The IV graphs showed a higher conductivity of quaternary nanocomposite. The cyclic voltammetry results revealed that the quaternary nanocomposite has a higher specific capacitance 500 Fg-1 as compared to binary nanocomposites 134 F g?1 (PANI-Pr2O3), 143 F g?1 (PANI-Co3O4), 256 F g?1 (PANI-NiO), and PANI (90.8 F g?1) at a scan rate of 5 m Vs?1. The GCD results also showed that the quaternary nanocomposite has a higher specific capacitance of 905 F g?1 at current density 1 A g?1 with maximum energy density and power density of 87.99 kWhkg-1 and 2.6 k W kg?1, respectively. The EIS curve also confirmed that the quaternary nanocomposite has a lower polarization resistance (Rp) and solution resistance (Rs). The higher capacitance of quaternary nanocomposite can facilitate ion transfer, and the formation of its core-shell structure flourish to enhance surface-dependent electrochemical properties. Furthermore, this study gives a novel research idea to manufacture electrode materials for supercapacitors. 相似文献
13.
Developing appropriate stable electroactive electrode materials for supercapacitor application is the challenging issue, which attracts enormous attention in recent decades. In this regard, Fe3O4 nanoparticles are firstly synthesized on chitosan/graphene oxide-multiwall carbon nanotubes (CS/GM/Fe3O4). Then, polyaniline (PANI) is grafted on it via in situ chemical polymerization and named as CS/GM/Fe3O4/PANI. The as-prepared nanocomposites are characterized by Field emission scanning electron microscopy, Fourier transform infrared spectroscopy, X-ray diffraction, X-ray photoelectron spectroscopy, and energy dispersive X-ray spectroscopy. The capacitive properties of the electrodes are investigated in a three electrode configuration in 0.5 M Na2SO4 electrolyte by various electrochemical techniques. The specific capacitance of CS/GM/Fe3O4/PANI electrode is 1513.4 Fg−1 at 4 Ag−1 which is 1.9 times higher than that of CS/GM/Fe3O4 (800 Fg−1). Meanwhile, the electrodes exhibit appropriate cycle life along with 99.8% and 93.95% specific capacitance at 100 Ag−1 for chitosan/GO-CNT/Fe3O4 and polyaniline grafted chitosan/GO-CNT/Fe3O4, respectively. 相似文献
14.
《Ceramics International》2019,45(12):14634-14641
Co3O4/melamine-derived carbon sponge (MCS) nanocomposite in which wrinkled ball-in-dodecahedral Co3O4 nanoparticles derived from ZIF-67 were homogeneously dispersed on the interconnected MSC was fabricated via a simple immersion and thermolysis route. As-prepared ultralight Co3O4/MCS possessed mechanically robust characteristic and unique 3D macroporous framework anchored with corrugated Co3O4 dodecahedra. Utilized as a pseudocapacitor electrode, Co3O4/MCS hybrid exhibited a great specific capacitance of 1409.5 F g−1 at the current density of 0.5 A g−1 and excellent long-term cycling stability of 93.2% after 1000 charge/discharge cycles, which might be ascribed to the synergistic effect of the inherent high redox activity from Co3O4 polyhedra combined with excellent electrical conductivity of MCS. This work demonstrates that tunable structure design and rational morphology control are efficient approaches for manufacturing novel electrode materials with extraordinary electrochemical performance. 相似文献
15.
Huiyu Chen Jinpeng Wang Fan Liao Xingrong Han Yanfei Zhang Chunju Xu Li Gao 《Ceramics International》2019,45(9):11876-11882
Uniform and porous Mn-doped Co3O4 microspheres (Mn@Co3O4 MSs) assembled with many nanoparticles (NPs) were prepared through an initially solvothermal reaction and subsequent annealing treatment at 550 oC in air. These Mn@Co3O4 MSs had an average diameter of about 9?μm and possessed a BET specific surface area of 70.4?m2/g. The pore diameter was mainly centered at 12.3?nm and the mean pore size was measured to be 15?nm. When the Mn@Co3O4 MSs were used as electrode material for supercapacitors, the electrochemical performances were assessed in 2?M KOH aqueous solution using a typical three-electrode configuration. Such Mn@Co3O4-MSs-modified electrode exhibited a highly specific capacitance of 773?F/g at 1 A/g, 62.7% rate capability at 16 A/g, and 73.9% capacitance retention of its original value after 5000 cycles at 5 A/g. The excellently electrochemical behaviors indicate that such Mn-doped Co3O4 MSs can be used as a superior electrode material for advanced supercapacitors in the future. The current synthesis strategy is facile and can be further employed to prepare other electrode materials with outstanding electrochemical performances. 相似文献
16.
以Bi(NO3)3·5H2O、Co(CH3COO)2·4H2O为原料,采用化学沉淀-水热法制备了Co3O4-Bi2O2CO3异质结构复合半导体光催化剂,并通过X射线衍射仪(XRD)、扫描电镜(SEM)、X射线光电子能谱(XPS)、紫外可见漫反射光谱(DRS)、荧光光谱(PL)等手段对所合成的复合型催化剂进行了理化性能表征。研究结果表明:引入Co3O4没有改变Bi2O2CO3物相结构,但促进了Bi2O2CO3 对可见光的吸收能力,提高了Bi2O2CO3表面吸附氧物种的数量,抑制了光生载流子复合。复合光催化剂对罗丹明B(RhB)的光催化脱色实验显示引入Co3O4能够明显提高Bi2O2CO3催化剂的光催化脱色能力。尤其是Co3O4引入量为0.6%的Co3O4-Bi2O2CO3样品对罗丹明B染料的光催化脱色率可达到97%(模拟日光照射30min)。本文为复合型光催化剂制备提供了简单易行的技术路线,制备的新型半导体复合光催化剂Co3O4-Bi2O2CO3在环境净化方面表现出了较好的应用前景。 相似文献
17.
Mesoporous Co3O4 (meso-Co3O4) and Co3O4 nanoparticles supported on mesoporous silica SBA-15 (Co/SBA-15) were prepared by hydrothermal synthesis and an impregnation method, respectively. Although the as-prepared meso-Co3O4 had mesopores and a higher surface area comparable to that of Co/SBA-15, its catalytic activity for N2O decomposition was much lower than that of Co3O4/SBA-15. The low catalytic activity of meso-Co3O4 mainly stems from the drastic decrease of the meso-Co3O4 surface area under the reaction condition used. On the other hand, Co/SBA-15 maintained its high surface area and mesopores with the aid of a robust silica support. This finding indicates that Co3O4 supported by a support is much more stable and efficient than meso-Co3O4 under N2O decomposition reaction conditions. 相似文献
18.
通过在NH4F+H2O的乙二醇溶液中阳极氧化铁箔,制备了纳米多孔结构的铁氧化物(Fe2O3–Fe3O4),然后在纳米多孔中电沉积镍,再经过400°C退火0.5 h,获得了镍与纳米多孔氧化铁的复合材料(Fe2O3–Fe3O4/Ni)。考察了电流密度和时间对镍沉积的影响。用扫描电镜、能谱仪、X射线衍射仪表征了复合材料的表面形貌、元素组成和物相,测试了其电化学性能并与未经电沉积镍的纳米多孔氧化铁(Fe2O3–Fe3O4)比较。结果表明,氧化铁由Fe2O3和Fe3O4组成。镀镍的最佳电流密度为2.0 m A/dm2,时间30 s。该纳米多孔Fe2O3–Fe3O4/Ni复合材料作为锂离子电池负极材料表现出更好的电化学性能──经过50次充放电循环后的放电比容量仍有438.3 m A·h/g,而Fe2O3–Fe3O4电极的放电比容量仅为110.6 m A·h/g。Fe2O3–Fe3O4/Ni电极的循环稳定性和倍率性能优异。 相似文献
19.
《Ceramics International》2020,46(10):15793-15800
We successfully synthesized a novel core-shell hybrid metal oxide via a simple one-step hydrothermal method without annealing. This composite of Co3O4 particles covered with SnO2–SnO (Co3O4@SnO2–SnO) predicted better performance compared to pure Co3O4, which strongly depends on the synthetic temperature. The Co3O4@SnO2–SnO prepared at a temperature of 250 °C (labeled Co3O4@SnO2–SnO-250) exhibited an outstanding specific capacitance of 325 F g−1 under the current density of 1 A g−1, which was much higher than those of Co3O4 (12.6 F g−1) and other composites. Additionally, the sample also exhibited good cycle stability performance with a retention rate of 100% after 5000 cycles at a current density of 5 A g−1. Through X-ray photoelectron spectroscopy analysis, the presumed mechanism was that Sn-Ox decreases the surface electron densities of Co3O4, which is beneficial to OH− adsorption and specific capacitance improvement, and the synthetic temperature had a strong impact on the microstructure and thus on the surface electron densities. The most.obvious finding to emerge from this study is that the specific capacitance can be improved through adjusting the surface electron densities of transition metal oxides. 相似文献
20.
采用模板和液相沉淀两种方法制备了锰的氧化物,XRD的测试结果表明,两种方法制备的锰氧化物分别为MnO2和Mn3O4。从TEM图可以看出,模板法制备的MnO2为直径为5~8nm左右的颗粒,而用液相沉淀制备的Mn3O4形貌为直径约为10nm左右的纤维棒。循环伏安和充放电测试结果都表明MnO2是更好的超电容器的电极材料。MnO2和Mn3O4在200mA·g-1电流密度下的放电比电容分别为157.5和145.0F·g-1,经过500次充放电后比电容分别为132.5和125.0F·g-1,充放电效率分别为64.9%和63.7%。 相似文献