共查询到18条相似文献,搜索用时 125 毫秒
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采用溶胶-凝胶法和水热合成反应法分别制备了氧化钌和氧化锰电极材料。进而采用胶体法制备了不同配比的氧化钌/氧化锰复合电极材料。利用扫描电镜和X射线衍射仪分别对电极材料的形貌及其结构进行表征。通过循环伏安法、恒流充放电、交流阻抗谱对复合电极进行电化学性能测试。结果表明:在氧化钌中加入适量的氧化锰的有助于降低氧化钌的成本和提高氧化钌的阻抗特性,当氧化锰的含量为60wt%时,在38%的H2SO4溶液中,扫描速度为20mV/s时,复合电极的比电容为438F/g,内阻为0.304Ω,且在经过300次循环充放电后,比容量仍保持92.5%,可作为较理想的超级电容器电极材料。 相似文献
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在三氯化钌(RuCl3)水溶液中,采用循环伏安法在铜电极表面电沉积氧化钌(RuO2)作为超级电容器电极材料。为了提高材料的电化学性能,在电沉积液中引入了氧化石墨烯(GO)水溶液,制备出RuO2/GO复合电极。采用扫描电镜(SEM)观察两种电极的表面形貌,发现氧化钌及其复合电极经60℃干燥处理1 h后,颗粒更均匀且存在明显的多孔特征,电极材料具有良好的表面特性。电化学测试结果表明,扫描速度为0.1 V/s、工作电位窗口为1 V时,两种电极比电容分别为636.5和938 F/m2,功率密度分别为31.83和46.9 W/m2。因此,RuO2/GO复合电极具有较好的电容特性,适合用作超级电容器电极材料。 相似文献
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超电容器活性炭/炭黑复合电极电容特性研究 总被引:3,自引:0,他引:3
为制备实用化的超电容器,对活性炭材料进行了表征,详细描述了活性炭/炭黑复合电极的制备工艺。通过循环伏安法和恒电流充电法,对活性炭/炭黑复合电极在水系电解液中的电容行为进行了研究。结果表明:活性炭的BET比表面积达1 654 m2/g,具有合理的孔径分布,主要在2 nm附近。添加高比表面积、高导电性纳米级炭黑制备的活性炭/炭黑复合电极具有优良的电容行为和较好的功率特性,复合电极的比容量达到102.4 F/g。此外还对孔径分布与电容的关系进行了阐述。 相似文献
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有机双电层电容器用活性炭电极的修饰 总被引:5,自引:2,他引:3
利用石墨、炭黑、碳纳米管三种导电碳材料,对高比表面积活性炭进行掺杂修饰,制备有机电解液双电层电容器用薄膜电极。经电化学测试发现,在 1 mol/L 的 LiPF6/EC-DEC(体积比 1∶1)溶液中,经不同导电材料修饰后的活性炭电极,其单电极比容量和大电流充放电性能均有较大改善。其中,掺杂 10%(质量分数)碳纳米管的活性炭电极,在 330 mA/g 电流密度下的单电极比容量可达 81 F/g,比未掺杂活性炭电极 60 F/g 的比容量提高了 35%;电流密度从 60 mA/g 增至 330 mA/g,该电极的容量保持率为 79.4%。 相似文献
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以Mn(NO3)2、活性中间相碳微球(活性MCMB)为原料,采用KBrO3氧化法,成功制备了MnO2/活性MCMB新型复合电极材料;以该材料制成电极,并以质量分数为30%的KOH溶液为电解液,组装成扣式电容器。通过XRD和SEM分析了MCMB,活性MCMB及MnO2/活性MCMB的晶相结构和表面形态;采用循环伏安、交流阻抗和恒流充放电法研究了电容器的电容性能。结果表明:以MnO2/活性MCMB复合电极制成的电容器电容性能优良。在0.5A/g电流密度下,其充放电曲线表现出典型的电容行为,初始比容量高达403.5F/g,相应能量密度为12.5Wh/kg;其循环伏安曲线关于零电流线对称,呈现为较规则的矩形;其等效串联电阻约为0.7Ω。 相似文献
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Nicolas Brun Savari R. S. Prabaharan Mathieu Morcrette Clément Sanchez Gilles Pécastaings Alain Derré Alain Soum Hervé Deleuze Marc Birot Rénal Backov 《Advanced functional materials》2009,19(19):3136-3145
By using Si(HIPEs) as hard, exotemplating matrices, interconnected macro‐/microporous carbon monolith‐type materials with a surface area of around 600 m2 g?1 are synthesized and shaped. The carbonaceous foams exhibit a conductivity of 20 S cm?1, addressed with excellent mechanical properties (Young's modulus of 0.2 GPa and toughness of 13 J g?1, when the carbon core is optimized). The above‐mentioned specificities, combined with the fact that the external shape and size can be easily designed on demand, are of primary importance for applications. The functionality of these carbonaceous monoliths is tested as both an electrochemical capacitor and a lithium ion negative electrode. The electrochemical capacitors' voltage–current profiles exhibit a non‐ideal rectangular response, confirming the double‐layer behavior of the carbon studied, while the charge‐discharge current profile of the electric double‐layer capacitor is directly proportional to the scan where the current response during charge and discharge exhibits high reversibility. When acting as a lithium ion negative electrode, after initial irreversibility, a good cyclability is obtained, associated with a stable capacity of 200 mA h g?1 during the first 50 cycles at a reasonable current density (C/10). 相似文献
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Multifunctional carbon materials are prepared for application as an active electrode material in an electrochemical capacitor displaying both charge storage and binder properties. The synthesis of the materials involves the functionalization of high surface area Black Pearls 2000 carbon black by a covalent attachment of polyacrylic acid. The polyacrylic acid polymer is formed by atom transfer radical polymerization using 1‐(bromoethyl)benzene groups initially bonded to the carbon by spontaneous grafting from the corresponding diazonium ions. The grafting of 1‐(bromoethyl)benzene and polyacrylic acid is confirmed by thermogravimetric analysis, Fourier transform infrared spectroscopy, energy‐dispersive X‐ray spectroscopy, and nitrogen gas adsorption isotherm. The composite electrode films prepared from the modified carbon are more hydrophilic and have better wettability in an aqueous electrolyte than the one prepared with the unmodified carbon. The modified electrodes also show a higher specific capacitance (≈140 F g?1), a wider working potential window (1.5 V) and excellent specific capacitance retention upon cycling (99.9% after 5000 cycles) in an aqueous 0.65 m K2SO4 electrolyte. Moreover, a relatively high specific capacitance (≈90 F g?1) is maintained at a scan rate of 1000 mV s?1 with the polyacrylic‐acid‐modified carbon electrode. 相似文献