当前位置: X-MOL 学术J. Electroanal. Chem. › 论文详情
Our official English website, www.x-mol.net, welcomes your feedback! (Note: you will need to create a separate account there.)
Electrochemical investigation on high-rate properties of graphene nanoplatelet-carbon nanotube hybrids for Li-ion capacitors
Journal of Electroanalytical Chemistry ( IF 4.5 ) Pub Date : 2020-04-01 , DOI: 10.1016/j.jelechem.2020.114060
Youngkwon Kim , Sang Cheol Woo , Churl Seung Lee , Ji Sun Park , Hyungeun Seo , Jae-Hun Kim , Jun Ho Song

Abstract Li-ion capacitors (LICs) are considered a bridging electrochemical energy device between Li-ion batteries and supercapacitors. Graphene nanoplatelet (GNP)‑carbon nanotube (CNT) hybrid materials can be a good candidate for negative electrode materials used in LICs. The rate performance of LIC negative electrodes plays a key role in increasing the power density of LICs. In this study, the Li storage kinetics of a GNP-CNT hybrid electrode was investigated. CNTs were directly grown on the GNP surfaces through chemical vapor deposition via transition metal oxide seeding. Natural graphite, GNP, and mixture (GNP and CNT) electrodes were used as the control electrodes. The kinetics was evaluated using electrochemical analysis tools such as galvanostatic charge-discharge cycling at various current densities, cyclic voltammetry, galvanostatic intermittent titration technique, and electrochemical impedance spectroscopy. The results revealed that the direct growth of CNTs on the GNP surfaces led to strong contact between these materials. This contact could play a pivotal role in the improvement of reversible Li storage kinetics characterizing negative electrodes for high-power LICs.

中文翻译:

用于锂离子电容器的石墨烯纳米片-碳纳米管杂化物的高倍率性能的电化学研究

摘要 锂离子电容器 (LIC) 被认为是锂离子电池和超级电容器之间的桥梁电化学能源装置。石墨烯纳米片 (GNP)-碳纳米管 (CNT) 混合材料可以成为 LIC 中使用的负极材料的良好候选材料。LIC 负极的倍率性能在提高 LIC 的功率密度方面起着关键作用。在这项研究中,研究了 GNP-CNT 混合电极的锂储存动力学。通过过渡金属氧化物种子的化学气相沉积,碳纳米管直接生长在 GNP 表面上。天然石墨、GNP 和混合物(GNP 和 CNT)电极用作控制电极。使用电化学分析工具评估动力学,例如各种电流密度下的恒电流充放电循环、循环伏安法、恒电流间歇滴定技术和电化学阻抗谱。结果表明,碳纳米管在 GNP 表面的直接生长导致这些材料之间的强烈接触。这种接触可以在改善表征高功率 LIC 负极的可逆锂储存动力学方面发挥关键作用。
更新日期:2020-04-01
down
wechat
bug