共查询到18条相似文献,搜索用时 78 毫秒
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本文以氯化钠为硬模板、硝酸镍为金属源、葡萄糖为碳源,在氮气气氛中于750 oC通过一步热解法合成嵌镍碳纳米片,然后经酸处理得到多孔碳纳米片. 通过扫描电镜(SEM)、透射电镜(TEM)、拉曼光谱(Raman)和比表面积测定(BET)表征多孔碳纳米片的形貌和结构. 结果显示:多孔碳纳米片孔分布均匀,孔径大小均一;经过酸处理后,碳材料的石墨化程度降低;具有较大的比表面积(约340 m2•g-1). 电化学测试表明,电极在100mA•g-1电流密度下,经过200周循环放电后比容量可维持在309.4 mAh•g-1,甚至在1000 mA•g-1 的大电流下其放电比容量仍然可达到173mAh•g-1,表现出良好的循环稳定性和倍率性能,其在钠离子电池负极材料方面具有潜在的应用前景. 相似文献
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首先采用溶液法在碳布上生长Co-MOF二维纳米片,通过高温退火和刻蚀后得到MOF衍生多孔碳纳米片。以Co-MOF衍生的多孔碳纳米片/碳布(CNS/CC)作为碳基骨架,采用电化学沉积法负载高活性氮掺杂石墨烯量子点(N-GQDs),制备得到分级多孔结构的N-GQD/CNS/CC复合材料。组装成自支撑且无粘结剂的N-GQD/CNS/CC电极,当电流密度为1 A·g~(-1)时,其比电容高达423 F·g~(-1)。通过储能机制和电容贡献机制的研究表明,在碳纤维上原位生长的具有高双电层电容的CNS和表面负载具有高赝电容的N-GQDs之间相互协同作用,使得N-GQD/CNS/CC电极具有高电容性能,是一种理想的超级电容器电极材料。电极材料的高导电、分级多孔结构有利于电子的传输和电解质离子的扩散,具有良好的动力学性能,能快速充放电和具有优异的倍率特性。将电极组装成对称型超级电容器,功率密度为250 W·kg~(-1)时对应的能量密度达到7.9 Wh·kg~(-1),且经过10 000次循环后电容保持率为91.2%,说明氮掺杂石墨烯量子点/MOF衍生多孔碳纳米片复合材料是一种电化学性能稳定的具有高电容性能的全碳电极材料。 相似文献
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自掺杂氮的多孔交联碳纳米片(N-ICNs)是将蒲公英种子通过一步活化碳化法制备的.蒲公英种子本身富含氮,不需要进行额外的掺杂处理,可以作为理想的碳前驱体.通过X射线衍射(XRD)、扫描电子显微镜(SEM)、透射电子显微镜(TEM)对所制备的碳材料的微观形貌和组成成分进行了表征.基于高含氮量(2.88%),N-ICNs在1 A·g-1下具有337 F·g-1的比电容和优异的倍率性能.此外,由N-ICNs组合成的对称型超级电容器在操作电压范围为0~2 V时具有很高的能量密度(25.3 Wh·kg-1)和功率密度(900 W·kg-1),并且在循环10000次后仍具有98%的电容保持率.因此,N-ICNs将是一种非常理想的电极材料. 相似文献
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本工作基于工业炼油产品沥青,开发了一种无金属、氮和硫共掺杂多孔碳纳米片(NSPC)的合成方法。获得的多孔碳纳米片具有高比表面积(339 m2·g-1)和优异的固硫能力。同时,高含量氮、硫共掺杂可以有效增强碳材料的导电性,同时促进多硫化物的高效催化转化。通过熔融法固硫后,制备得到的NSPC/S电极具有较高的比容量和优异的循环稳定性(在0.6C电流密度下,200次循环后容量为762 mAh·g-1),实现了高含量氮和硫共掺杂的二维多孔碳材料的快速批量生产并用于高性能锂硫电池正极材料。 相似文献
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氮掺杂碳材料是近年来新兴的一种多孔材料,具有高比表面积、高导电性、高活性和良好的稳定性,但制备过程繁琐,成本较高.本文简要介绍了采用廉价生物质制备氮掺杂碳材料的方法,生物质来源广泛、安全无毒且成本低廉,虾壳、藻类、果壳和毛发等生物废弃物中所含木质素、蛋白质和氨基酸等提供了丰富的N、P、C等元素,既可作为氮源也可以作为碳源.生物质经过活化可制成生物质基氮掺杂碳材料,由于N元素改变了碳材料的电荷密度和表面理化性质,提供更多活性位点,使材料不但具有优异的电化学性能,又可作为载体均匀负载金属催化各类反应,能够得到比商业催化剂更好的催化性能.重点介绍生物质基氮掺杂碳材料在燃料电池和超级电容器领域的应用,讨论了生物质基氮掺杂碳材料的制备和应用存在的问题,展望其未来的发展趋势. 相似文献
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Jiangmin Jiang Ping Nie Shan Fang Yadi Zhang Yufeng An Ruirui Fu Hui Dou Xiaogang Zhang 《中国化学快报》2018,29(4):624-628
A high performance hybrid ion capacitors has been developed by using B, N dual-doped 3D superstructure carbon cathode and prelithiated graphite anode. 相似文献
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The mesoporous carbon material with large pore volume and high surface area by a simple situ MgO template method is synthesized, which is utilized as cathode to assemble a high performance lithium ion capacitor. 相似文献
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《中国化学快报》2020,31(9):2219-2224
Sodium ion hybrid capacitors are of great concern in large-scale and cost-effective electrical energy storage owing to their high energy and power densities, as well as natural abundance and wide distribution of sodium. However, it is difficult to find a well-pleasing anode material that matches the high-performance cathode materials to achieve good energy and power output for sodium ion hybrid capacitors. In this paper, nitrogen and sulfur co-doped nanotube-like carbon prepared by a simple carbonization process of high sulfur-loaded polyaniline nanotubes is introduced as the anode. The assembled sodium ion half cell based on the optimal nanotube-like carbon delivers a high reversible capacity of ∼304.8 mAh/g at 0.2 A/g and an excellent rate performance of ∼124.8 mAh/g at 10 A/g in a voltage window of 0.01–2.5 V (versus sodium/sodium ion). For the hybrid capacitors assembled using the optimal nanotube-like carbon as the anode and high-capacity activated carbon as the cathode, high energy densities of ∼100.2 Wh/kg at 250 W/kg and ∼50.69 Wh/kg at 12,500 W/kg are achieved. 相似文献
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Guofu Ma Zhiguo Zhang Hui Peng Kanjun Sun Feitian Ran Ziqiang Lei 《Journal of Solid State Electrochemistry》2016,20(6):1613-1623
In this work, the micromolecule l-glutamic acid (Glu) is employed as nitrogen-rich precursor to prepare a novel porous carbon, and ZnCl2 is used as activating agent to improve the surface area and electrochemical performance of the carbon. The nitrogen content of the carbon (Glu-2.5) prepared by Glu and ZnCl2 with a mass ratio of 1:2.5 retains as high as 7.1 % at an activation temperature of 700 °C. The surface area and pore volume of Glu-2.5 are 1007.4 m2 g?1 and 0.57 cm3 g?1, respectively. Glu-2.5 exhibits a high specific capacitance of 330.6 F g?1 in 2 M KOH electrolyte at the current density of 1 A g?1and good cycling stability (89 % retention of capacitance after 5000 charge/discharge cycles). More importantly, the assembled symmetric supercapacitor using Glu-2.5 as electrodes reveals a high energy density (16.7 Wh kg?1) under the power density of 404.7 W kg?1. Owing to its inherent advantages, Glu-2.5 could be a promising and scalable alternative applied to energy storage/conversion. 相似文献
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选取溴代噻唑和三乙炔基苯为单体,利用聚合反应自下而上构建含噻唑共轭微孔聚合物(NSCMP),通过热解和KOH活化热解NSCMP制备了氮、硫杂原子硬炭(NSHC)和活化NSHC(KNSHC)。利用扫描电子显微镜、能量色散谱、氮气吸附-脱附和恒流充放电等表征2个样品的结构与电化学性能。研究表明KNSHC中N和S的质量分数分别为10.42%和2.23%,KNSHC比表面积高达2 140 m2·g-1。在0.2 A·g-1电流密度下循环500次后KNSHC和NSHC的可逆比容量分别为946.2和493.7 mAh·g-1。KNSHC的优异电化学性能归因于其独特的孔结构和氮、硫杂原子的协同作用。 相似文献
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Microporous carbon aerogel prepared through ambient pressure drying route as anode material for lithium ion cells 下载免费PDF全文
Ancy Smitha Alex Ananda Lekshmi M.S. Sekkar V. Bibin John Gouri C. Ilangovan S.A. 《先进技术聚合物》2017,28(12):1945-1950
Carbon aerogel synthesized through a cost‐effective and easy method was evaluated and found to be a promising anode material for lithium ion cells. Carbon aerogel was prepared by carbonizing resorcinol–formaldehyde (RF) aerogel under inert atmosphere. Resorcinol–formaldehyde aerogel in turn was prepared through sol gel polymerization of resorcinol with formaldehyde using sodium carbonate as catalyst adopting ambient pressure drying route. The structure and the morphology of the prepared carbon aerogel are investigated using X‐ray diffraction (XRD), scanning electron microscopy (SEM) and transmission electron microscopy (TEM) and surface area determined using N2–Brunauer–Emmett–Teller (BET) method. The TEM images reveal microporous morphology of the carbon aerogel particles. The evaluation of carbon aerogel as an anode material revealed promising specific capacity synergized with outstanding cyclability. The first cycle specific capacity was 288 mAh/g with an efficiency of 63% at C/10 rate. The material retained a capacity of 96.9% of the initial capacity with about 100% efficiency after 100 cycles, showing the excellent cyclability of the material. Copyright © 2017 John Wiley & Sons, Ltd. 相似文献
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碳纳米纤维负载铁钴镍硼化物可控制备及其电催化析氢性能研究 《燃料化学学报》2003,48(10):1270-1280
通过乙醇催化燃烧法制备了碳纳米纤维(CNFs),采用化学沉积法在CNFs载体上负载铁钴镍硼化物(FeCoNiB),并以多种测试手段对其表征,研究了化学沉积工艺条件对FeCoNiB粒径、分散、成分及结构的影响,建立了碳纳米纤维负载的铁钴镍硼化物(FeCoNiB/CNFs)可控制备方法。采用电化学测试手段研究了FeCoNiB/CNFs在碱性环境下的氢气析出反应(HER)催化性能。结果表明,在100 mA/cm2的电流密度下,FeCoNiB/CNFs的过电位仅为366 mV,塔菲尔斜率低至41 mV/dec;在持续10 h的稳定性测试中电位衰减幅度很小,基本保持不变。这说明FeCoNiB/CNFs制备成本低,但其高稳定性可媲美贵金属的高催化活性HER催化剂;该研究可为非贵金属HER催化剂的研制及低成本电解水制氢技术的规模化应用提供参考。 相似文献
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《中国化学快报》2020,31(9):2215-2218
Potassium-ion capacitors (KICs) emerge as a promising substitute for the well-developed lithium-ion capacitors (LICs), however, the energy density of KICs is below expectations because of lacking a suitable electrical double-layer positive electrode. Using chemical activation of the Aldol reaction product of acetone with KOH, we synthesized a porous carbon with a Brunauer-Emmett-Teller surface area of up to 2947 m2/g and a narrow pore size distribution ranging from 1 nm to 3 nm. Half-cell (versus potassium metal) test demonstrates that this porous carbon has high capacitive performance in K+ based organic electrolytes. Furthermore, a novel KIC fabricated by this porous carbon as the cathode, yields high values of energy density and power density. The processes used to make this porous carbon are readily low-cost to fabricate metal-ion capacitors. 相似文献