标题(中文):
铁复合纳米粒子原位封装在生物质衍生的碳纳米管中,用于高性能超级电容器
标题(英文):
In-Situ Encapsulation of Iron Complex Nanoparticles into Biomass-Derived Heteroatom-Enriched Carbon Nanotubes for High-Performance Supercapacitors
刊物名称及期号、页码:
Advanced Energy Materials, 2018, 1803221(1-8)
作者姓名(中文):
张晶晶,赵华平,李俊,金辉乐,* 余小春, 雷勇*, 王舜*
作者姓名(英文):
Jingjing Zhang, Huaping Zhao, Jun Li, Huile Jin,* Xiaochun Yu, Yong Lei*, and Shun Wang*
摘要(英文):
The capacitive performance of carbon materials could be enhanced by means of increasing the number of active sites, the surface area and the porosity as well as through incorporating heteroatoms into the carbon framework. However, the charge storage through electric double layer mechanism results in limited increase in capacitance of modified carbon materials. Herein, a simple and straightforward strategy is introduced for in-situ synthesizing iron complex (FeX, which X includes O, C, and P) nanoparticles encapsulated into biomass-derived N, P-codoped carbon nanotubes (NPCNTEs), using a natural resource, egg yolk, as heteroatom-enriched carbon sources and potassium ferricyanide as the precursor for iron complex. Compared with heteroatom-enriched carbon nanomaterials derived from the carbonization of egg yolk, the synergetic function of the heteroatom doping, the incorporation of FeX nanoparticles, and the unique structural characteristics endows the as-prepared sample with largely improved electrochemical performance. As expected, FeX@NPCNTs hybrid nanomaterials exhibit superior capacitive performance, including high specific capacitance, impressive rate performance, and excellent cycle stability. Using the as-prepared FeX@NPCNTs hybrid nanomaterials as electroactive materials, a symmetric supercapacitor with high capacity and a long-term cyclability is finally demonstrated (more than 99% capacitance retention after 50,000 cycles at a current density of 10 A/g).
图1 复合材料合成路线
图2 复合材料的表征
研究现状(中文):
超级电容器在解决化石燃料消耗和环境污染方面问题具有巨大的潜力。新型能量储存材料引起了广泛关注,特别是在超级电容器材料的高能量密度性能方面。多孔碳由于具有高导电性、大比表面积和高化学稳定性,在超级电容器电极材料中是热门候选材料。杂原子掺杂的碳材料在能源领域中显示出巨大的优势,这是由于异质原子与宿主原子之间电荷极化和电负性/电子自旋密度的差异造成的。因此,掺杂杂原子(N、P、B、S等)可以通过改变带隙和表面电子性质(润湿性、电子云分布等)来提高电化学活性。在这项研究中,我们直接以富含杂原子的生物质为碳基,以铁氰化钾作为铁络合物的前体。引入了一种简单直接的策略,用于原位合成铁络合物(FeX,其中包括O,C和P)纳米粒子包裹在生物质衍生的N,P共掺杂碳纳米管(NPCNT)中,与衍生自蛋黄碳化的富含杂原子的碳纳米材料相比,杂原子掺杂的协同作用,FeX纳米颗粒的结合和独特的结构特征赋予所制备的样品优异的电化学性能。使用所制备的FeX @ NPCNTs杂化纳米材料作为电活性材料,最终证明了具有高容量和长期循环特性的对称超级电容器(在10 Ag-1的电流密度下,在50 000次循环后电容保持率超过99%)。在0.5 A/g时体积电容已达到1312.0 Fcm-3。
创新点(中文):
(1)复合材料合成条件温和、简单高效,有望宏量生产;
(2)利用N、P、Fe等重元素来提高碳材料的密度,增加材料的体积电容,克服了传统材料低密度对便携式器件发展的阻碍;
(3)一方面通过N,P等非金属杂原子的多重掺杂使得碳材料的非本征缺陷增加,进而增加电子的自旋密度以及电子云的不对称性,致使催化活性的提升;另一方面原位引入铁络合物增加材料的赝电容,同时结合碳纳米管的限域作用增加碳基材料的电化学稳定性。
DOI:10.1002/aenm.201803221
原文链接://onlinelibrary.wiley.com/doi/pdf/10.1002/aenm.201803221