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1.
利用原位聚合法制备了聚苯胺/有序介孔炭复合材料.通过恒流充放电、循环伏安和交流阻抗测试考察了不同聚苯胺含量对聚苯胺/有序介孔炭复合材料电化学性能的影响.研究表明:与纯的有序介孔炭和聚苯胺相比,聚苯胺/有序介孔炭复合材料具有更高的比容量,良好的稳定性和充放电循环性能.当聚苯胺质量分数为60%,电流密度为0.1A·g-1时,比容量可以达到409F·g-1.  相似文献   

2.
We report a wire-shaped three-dimensional(3D)-hybrid supercapacitor with high volumetric capacitance and high energy density due to an interconnected 3D-configuration of the electrode allowing for large number of electrochemical active sites,easy access of electrolyte ions,and facile charge transport for flexible wearable applications.The interconnected and compact electrode delivers a high volumetric capacitance(gravimetric capacitance)of 73 F cm−3(2446 F g−1),excellent rate capability,and cycle stability.The 3D-nickel cobalt-layered double hydroxide onto 3D-nickel wire(NiCo LDH/3D-Ni)//the 3D-manganese oxide onto 3D-nickel wire(Mn3O4/3D-Ni)hybrid supercapacitor exhibits energy density of 153.3 Wh kg−1 and power density of 8810 W kg−1.The red lightemitting diode powered by the as-prepared hybrid supercapacitor can operate for 80 min after being charged for tens of seconds and exhibit excellent electrochemical stability under various deformation conditions.The results verify that such wire-shaped 3D-hybrid supercapacitors are promising alternatives for batteries with long charge–discharge times,for smart wearable and implantable devices.  相似文献   

3.
In this work, we prepared a reduced graphene oxide (RGO)/poly(3,4-ethylenedioxythiophene) (PEDOT) hybrid composite with well defined nanostructure. The graphene oxide (GO) was first deposited on substrate through the Langmuir–Blodgett (LB) deposition, which provided a tunable and ordered GO arrangement on substrate. Then the GO LB films were reduced to RGO by following thermal treatment, and a ultrathin conducting polymer (CP) PEDOT was directly coated on RGO through a vapor phase polymerization process. The RGO/PEDOT nanocomposite exhibits excellent electrical conductivity about 377.2 S/cm. Electrochemical activity investigation revealed that this nanocomposite exhibits 213 F/g high specific capacitance at a 0.5 A/g current density and shows better capacitance retention rate than pure PEDOT. The detailed study also confirmed that the arrangement of RGO shows distinct influence on the electrical and electrochemical properties of obtained nanocomposite. Large area RGO/PEDOT nanocomposite with high conductivity and electrochemical activity can be deposited on different substrates. Such high conductivity and electrochemical activity RGO/CP nanocomposite shows promising application future in organic and flexible electrode materials for sustainable energy storage.  相似文献   

4.
《Materials Letters》2007,61(23-24):4627-4630
Pore surface of ordered mesoporous carbon (OMC) was coated with a thin layer of polyaniline by chemical polymerization of aniline monomers. Structure characterizations, such as N2 adsorption analysis, small angle X-ray diffraction and transmission electron microscopy, demonstrate that polyaniline is well distributed on the pore surface of OMC. As evidenced by constant current charge–discharge test, specific capacitance of polyaniline-coated ordered mesoporous carbon (PCOMC) reaches as high as 602.5 F/g, which is much higher than that of OMC, due to the incorporation of polyaniline onto the pore surface of OMC. However, the capacitive behavior deteriorated somewhat due to the narrowed pore size and extra faradiac reactions caused by the incorporation of polyaniline.  相似文献   

5.
An ordered mesoporous carbon. (OMC) synthesized by the soft-template method was activated by (a) CO2 at 900 degrees C for 4 h, (b) H2O at 800 degrees C for 20 min, and (c) H2O at 800 degrees C for 20 min followed by CO2 at 900 degrees C for 4 h to produce three micro-mesoporous carbons, A1, A2 and A3, respectively. Their pore structures were investigated by XRD, TEM, SEM and N-2 adsorption. Their electrochemical properties as the electrode materials of supercapacitors were investigated by cyclic voltammetry, galvanostatic charge-discharge and electrochemical impedance spectroscopy. Results indicated that the highly ordered 2D hexagonal original mesostructure of the OMC was well retained after activation. The increasing order of the extent of activation is A1相似文献   

6.
采用微湿含浸法制备了一系列具有不同比表面积和孔径分布的超级电容器有序中孔炭材料。采用液氮吸附脱附等温线、小角XRD以及TEM表征了有序中孔炭的孔结构,在1MEt4NBF4|PC电解液中测试了其电化学性能。结果表明,所制得的有序中孔炭的BET比表面积随糠醇加入量的增加先增加后减小,糠醇加入量少制得具有CMK-5结构的有序中孔炭,加入量多制得的CMK-3结构。电化学性能测试结果表明,在1mA·cm-2的充放电电流密度下各有序中孔炭材料比电容的大小顺序与其BET比表面积的大小顺序基本一致,具有CMK-3结构的有序中孔炭的倍率性能最好,并且也好于无序中孔炭的。  相似文献   

7.
The electrochemical synthesis of mesoporous ruthenium (Ru) films using sacrificial self‐assembled block polymer micelles templates, and its electrochemical surface oxidation to RuOx is described. Unlike standard methods such as thermal oxidation, the electrochemical oxidation method described here retains the mesoporous structure. Ru oxide materials serve as high‐performance supercapacitor electrodes due to their excellent pseudocapacitive behavior. The mesoporous architectured film shows superior specific capacitance (467 F g?1 Ru) versus a nonporous Ru/RuOx electrode (28 F g?1 Ru) that is prepared via the same method but omitting the pore‐directing polymer. Ultrahigh surface area materials will play an essential role in increasing the capacitance of this class of energy storage devices because the pseudocapacitive redox reaction occurs on the surface of electrodes.  相似文献   

8.
通过原位聚合法分别将无序介孔碳(DOMC)、有序介孔碳(OMC)掺杂到聚酰亚胺(PI)中制备DOMC/PI、OMC/PI杂化膜。利用FTIR、TEM、SEM和XRD等分析表征两种介孔碳材料的结构及其掺杂对杂化膜形貌和结构的影响,结合CO2和N2的渗透实验考评杂化膜的气体渗透性能。DOMC、OMC均具有孔隙结构,且与CO2分子之间存在相互作用,通过掺杂DOMC、OMC既能提高杂化膜的自由体积,又可促进杂化膜对CO2的优先选择吸附。表现为掺杂DOMC、OMC可有效改善PI膜的CO2、N2渗透性能和CO2/N2渗透选择性。随掺杂量的增加,杂化膜的CO2、N2渗透性能和CO2/N2渗透选择性均先增大后减小。另外,相较于OMC,DOMC具有更多孔隙结构和更大的比表面积,使DOMC/PI杂化膜的CO2、N2渗透性能优于OMC/PI杂化膜,但两种杂化膜的CO2/N2渗透选择性相近。  相似文献   

9.
Heteroatom doping is a promising strategy for improving the electrochemical performance of carbon materials. Herein, we spotlight an advantageous, simple, and efficient CVD synthesis of P-doped 3D cubic ordered mesoporous carbon (POMC) for the first time. The POMC was prepared by pyrolysis of acetylene/triphenylphosphine (C2H2/Ph3P) mixture at relatively low temperature over Fe-KIT-6 as a sacrificial template. The ensuing P-doped OMC showed an enhanced porous texture than an undoped counterpart with a specific surface area of 403.5 m2/g, pore volume of 0.545 cm3/g, average pore size of 4.64 nm and suitable heteroatom functionalities with P and O contents of 0.13% and 9.83%, correspondingly. The obtained POMC exhibited a much higher specific capacitance of 288F/g at 0.2 A/g (175F/g for OMC), good cyclic stability of 97.6 %, and good rate capability than pristine OMC in 6 M KOH. It is equivalent to or improved than various stated mono doped and even dual doped porous carbon electrodes. Furthermore, a symmetric supercapacitor (POMC//POMC) was fabricated with 1 M Na2SO4 aqueous neutral electrolyte exhibits high cycling stability (89.3%) even with a wide potential window (2.0 V) and offers a relatively high energy density (10.01 Wh/kg) with a power density of 300 W/kg.  相似文献   

10.
采用有机交联水性环氧树脂为碳源,以SBA-15为模板,制备了有序介孔碳(OMC),并对其电化学性能进行研究。透射电镜结果表明其具有典型的二维有序六角介孔结构,孔径大约为3nm。电化学测试结果表明OMC/Lac/Au电极对邻苯二酚具有很好的电催化氧化活性。将OMC应用于构建漆酶生物传感器,结果表明,传感器对邻苯二酚的线性检测范围为0.67~8.59μmol/L,灵敏度为0.349A/(mol/L),检测限为0.117μmol/L。  相似文献   

11.
Titanium planar sheet formed by a chemical polishing process and titania nanotube array formed by an electrochemical anodization process are used as electrode substrates, on which electroactive ruthenium oxides are deposited by an electroreduction and electrooxidation process for supercapacitor applications. Morphological characterization and electrochemical properties of the electrode substrates and ruthenium oxide electrodes have been investigated. Crystalline titania nanotube array shows a much higher electric double layer capacitance than titanium planar sheet due to its high surface area of nanotube walls. Additionally, the well-defined ruthenium oxide–titania/titanium nanotube array electrode exhibits a much higher redox supercapacitance and a lower capacitance decay than ruthenium oxide/titanium planar film electrode. Such a superior energy-storage performance of ruthenium oxide–titania/titanium is ascribed to highly accessible nanotube channels for the reversible redox reaction of ruthenium oxide. The modification strategy of ruthenium oxide electrode by introducing highly ordered nanotube array structure instead of planar film structure can significantly improve specific capacitance as well as cyclic charge-discharge stability.  相似文献   

12.
Metal–organic frameworks (MOFs) or coordination polymers (CPs) have been used as precursors for synthesis of materials. Unlike crystalline MOF, amorphous CP is nonspecific to metal cation species, therefore its composition can be tuned easily. Here, it is shown that amorphous CP can be used as general synthesis precursors of highly complex mixed metal oxide shells. As a proof of concept, Ni? Co coordination polymer spheres are first synthesized and subsequently transformed into seven‐layered Ni? Co oxide onions by rapid thermal oxidation. This approach is very versatile and can be applied to produce ternary and quaternary metal oxide onions with tunable size and composition. The Ni? Co oxide onions exhibit exceptional charge storage capability in aqueous electrolyte with high specific capacitance (≈1900 F g?1 at 2 A g?1), good rate capability, and ultrahigh cycling stability (93.6% retention over 20 000 cycles). A hybrid supercapacitor against graphene/multishelled mesoporous carbon sphere shows a high energy density of 52.6 Wh kg?1 at a power density of 1604 W kg?1 (based on active materials weight), as well as remarkable cycling stability.  相似文献   

13.
We report on the enhanced capacitive properties of a copper(I) oxide nanoparticle (Cu2O NP)-decorated multiwalled carbon nanotube (MWCNT) forest with nitrogen (N) doping. A careful in situ solid-state dewetting and plasma doping method was developed that ensured homogeneous decoration and contamination-free Cu2O NPs with N doping on the nanotube sidewalls. The morphology and structure of the hybrid materials were characterised by scanning electron microscopy, transmission electron microscopy, energy-dispersive spectroscopy, Raman spectroscopy and X-ray photoemission spectroscopy. The electrochemical performance of the hybrid materials was investigated by cyclic voltammetry and galvanostatic charge/discharge tests in a 0.1 M Na2SO4 electrolyte. The electrochemical tests demonstrated that the Cu2O NP/N-MWCNT electrode exhibits a specific capacitance up to 132.2 F g?1 at a current density of 2.5 A g?1, which is 30% higher than that of the pure MWCNT electrode. Furthermore, the electrode could retain the specific capacitance at 85% stability over 1000 cycles. These observations along with the simple assembly method for the hybrid materials suggest that the Cu2O NP/N-MWCNT could be a promising electrode for supercapacitor applications.  相似文献   

14.
MnO2为有前景的超级电容器正极材料,具有较高的理论比电容及良好的循环稳定性,但电子电导性不佳限制了其应用。采用一步水热法制备了还原氧化石墨烯(RGO)/NixMn1-x/2O2复合材料。通过XRD、SEM、TEM、FTIR、电化学分析等手段对制备的RGO/NixMn1-x/2O2物相组成、微观形貌和电化学性能进行了表征和分析。电化学测试结果表明:Ni元素的引入提高了MnO2的电容性能,以水热法制备的MnO2的比电容为66 F/g (扫描速度10 mV/s),而Ni元素掺杂量x=0.02时,Ni0.02Mn0.99O2比电容为111 F/g;材料中引入RGO后,RGO/NixMn1-x/2O2复合材料电容性能进一步提高,加入2wt%的RGO时,RGO/Ni0.02Mn0.99O2的比电容为136 F/g。RGO的引入提高了活性材料的电子迁移速率,Ni元素的掺杂造成了MnO2晶格中存在适量的点缺陷,提高了其导电性。以RGO/NixMn1-x/2O2为正极的超级电容器可同时具备双电层电容器和赝电容器的优点,以Ni掺杂MnO2和RGO的负载协同提高了该复合材料电化学性能。  相似文献   

15.
碳纳米管表面沉积氧化镍及其超电容器的电化学行为   总被引:11,自引:1,他引:10  
通过催化裂解法制备了碳纳米管并进一步制备了碳纳米管薄膜电极.基于该种材料的超电容器电极比容量达到36F/g.研究了在碳纳米管薄膜基体上使用电化学方法沉积氧化镍的新工艺,制备出碳纳米管和氧化镍的复合电极.电化学测试证明复合电极的比容量提高到52F/g以上且基于这种复合电极的超电容器具有极低的自放电率.  相似文献   

16.
An in-depth microstructural characterization was performed on manganese oxide materials that have been produced for electrochemical supercapacitor applications using a novel physical vapor deposition process. Manganese was e-beam evaporated and deposits as a combination of the cubic forms of Mn and MnO with a porous zigzag structure. The electrochemically oxidized sample that is used as the supercapacitor base material is tetragonal Mn3O4. An apparent active layer with increased sodium levels was imaged by STEM, lending some credence to the argument that the pseudocapacitance effect is based entirely on a surface layer of adsorbed sodium. Upon furnace annealing the zigzag structure near the free surface is destroyed and replaced with a columnar oxide layer of cubic MnO and tetragonal Mn3O4. This capping effect ultimately reduces the usable surface area and is thought to account for the reduction in capacitance seen on annealing.  相似文献   

17.
以中间相沥青为前驱体,经自挥发发泡法、KOH活化法制备的中间相沥青基活性泡沫炭作为超级电容器电极材料。采用扫描电镜、X射线衍射和低温(77K)N2吸附法对中间相沥青基活性泡沫炭的表面形貌和微观结构进行表征。中间相沥青基活性泡沫炭的比表面积为2700m2/g,总孔孔容为1.487cm3/g。通过恒流充放电、循环伏安和交流阻抗测试,考察了中间相沥青基活性泡沫炭作为超级电容器电极材料的电化学性能。在电流密度为0.02A/g时,中间相沥青基活性泡沫炭的比容量为240.48F/g,能量密度为33.4Wh/kg;在电流密度为5A/g时,比容量为166.68F/g,具有良好的电化学特性。  相似文献   

18.
Graphene has become a worldwide admired material among researchers and scientists equally due to its unique richness in mechanical strength,electrical conductivity,optical and thermal properties.Researchers have explored that the composite materials based on graphene and metal/metal oxide nanostructures possess excellent potential for energy storage technologies.In particular,supercapacitors based on such composite materials have engrossed the extreme interest of researchers for its rapid charging/discharging time,safe operation and longer cyclic constancy.Till now,several fabrication techniques for composite materials and their energy storage applications have been explored.Here,specially,we have concentrated on the hottest research progress for the fabrication of graphene oxide and metal/metal oxide nanocomposites.We also emphasized on the characteristics and properties of supercapacitors fabricated using these composite materials.Moreover,our study is focused on the specific capacitance and cyclic stability of various composites to haul out the most efficient material for supercapacitor applications.  相似文献   

19.
The concept of interfacial polymerization is utilized for the synthesis of polyaniline-phosphomolybdate (PAni-PMo12) molecular hybrids and it is well characterized. The electrical conductivity of the synthesized hybrid materials increases with increase in PMo12 wt%. The synthesized hybrid materials are evaluated as the active electrode materials for supercapacitor application. Cyclic voltammetric studies of the hybrid-modified electrode shows broad parallelogram-shaped peak as an evidence for pseudo-capacitive behaviour. The galvanostatic charge-discharge studies enlighten that interfacially synthesized hybrid materials loaded with PMo12 show relatively enhanced specific capacitance values than PMo12 free samples.  相似文献   

20.
《Materials Letters》2007,61(23-24):4639-4642
The pore structure and electrochemical performances of mesoporous carbons prepared by silica sol template method as electrode material for supercapacitor were investigated in this work. The pore size distribution of the mesoporous carbons changes from unimodal to bimodal and the mean pore size increases with the increase of silica sol/glucose ratio. The specific capacitance of the mesoporous carbons also increases with the increase of silica sol/glucose ratio. A novel technique named as template–chemical activation method, combining both template and chemical activation methods, is proposed, which can effectively control the pore structure, improving the electrochemical properties of the mesoporous carbon with improved porosity especially microporosity.  相似文献   

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