Hydrogen Sorption by Single-Walled Carbon Nanotubes with Metallic Species of Intended Distribution

具有预期分布金属形态的单壁碳纳米管吸氢

基本信息

批准号：
18560676
负责人：
NISHIMIYA Nobuyuki
金额：
$ 2.32万
依托单位：
Nihon University (2007)Toyohashi University of Technology (2006)
依托单位国家：
日本
项目类别：
Grant-in-Aid for Scientific Research (C)
财政年份：
2006
资助国家：
日本
起止时间：
2006 至 2007
项目状态：
已结题

来源：
https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-18560676/
关键词：
Single-walled carbon nanotube Metal modification Calorimetry Hydrogen storage material Specific surface area Rule of reversed stabilit 水素吸蔵材料カーボンナノチューブ

项目摘要

Hydrogen capacities of single-walled carbon nanotubes (SWCNTs), which were synthesized by arc-discharge between graphite rods having Ni-Y catalysts and were sono-chemically treated in nitric acid to be free of bundle-like structures and free from metallic species contaminated on arc-discharge, were less than 0.1 wt.% at room temperature and 0.1 MPa of hydrogen, that is, essentially zero.Metal modification was carried out by non-electrolytic plating or by thermal decomposition of organometallic compounds and hydrogen capacities were evaluated by Temperature Programmed Desorption (TPD) after deuterium was formed. High hydrogen capacities were observed when palladium, iron, nickel etc. or combinations of them were distributed on SWCNTs. Howeve4 hydrogen capacities of those SWCNTs which were in situ modified with metals on synthesis (PVD) were larger than the ones modified by the wet methods.Heats on combustion of SWCNTs modified with iron group elements significantly exceeded those of c … More arbons, which suggested that endothermic bonding was formed between SWCNTs and metals. The rule of reversed stability, which generally holds for metal hydrides, thus gives a prediction that SWCNTs modified with iron group elements were unstable enough to form stable hydrides, and that has been verified by the above-mentioned results. Since hydrogen capacities close to 1 wt% have been obtained for SWCNTs with low specific surface areas of 200 m2/g, practical hydrogen storage materials will be developed by increasing specific surface areas to 2,000 m2/g.Another in situ modification comprising chemical vapor deposition (CVD) gave promising nanocarbons when Mg-Ni or Mg-Fe powders were present The TPD analysis showed plausible higher hydrogen capacities for CVD samples than for PVD samples. Large scale synthesis is now under progress to evaluate the qualitative capacities by isothermal measurements.Hydrogen capacities were also imparted to B-C-N compounds with layered structures by similar metal modifications. Less

单壁碳纳米管 (SWCNT) 的氢容量，其通过具有 Ni-Y 催化剂的石墨棒之间的电弧放电合成，并在硝酸中进行声化学处理，使其不含束状结构且不含金属污染物质电弧放电时，在室温和0.1 MPa氢气下小于0.1 wt.%，即基本上为零。通过非电解电镀进行金属改性或通过有机金属化合物的热分解和氘形成后通过程序升温解吸（TPD）评估氢容量，当钯、铁、镍等或其组合分布在Howeve4的氢容量上时观察到高氢容量。金属合成（PVD）原位改性的SWCNT比湿法改性的SWCNT大。铁族元素改性的SWCNT的燃烧热显着显着超过了碳，这表明单壁碳纳米管和金属之间形成了吸热键合。逆稳定性规则通常适用于金属氢化物，因此可以预测铁族元素修饰的单壁碳纳米管是不稳定的，无法形成稳定的。氢化物，并且这已被上述结果所证实，由于具有 200 m2/g 的低比表面积的 SWCNT 已获得接近 1 wt% 的氢容量，因此具有实用性。储氢材料将通过将比表面积增加到 2,000 m2/g 来开发。另一种原位改性，包括化学气相沉积 (CVD)，当存在 Mg-Ni 或 Mg-Fe 粉末时，可以得到有前景的纳米碳。TPD 分析显示，氢容量可能更高CVD 样品的性能优于 PVD 样品的性能，目前正在进行大规模合成，以通过等温测量来评估定性容量。类似的金属也赋予了具有层状结构的 B-C-N 化合物氢容量。修改较少。