摘要
根据微孔填充和吸附理论,发现一种微观结构优化工艺,即通过“HNO3/HCl HNO3/HF 空气氧化”三步法处理碳纳米管,可以使管两端绝大部分封闭的端口打开,管平均内径由 5nm扩大到 20nm,管壁大大变薄,团聚的碳纳米管束成为独立存在的碳纳米管,比表面积提高约 2. 5 倍, 由 180. 5m2/g 提高到649.5m2/g,质量储氢分数提高约 7 倍,由 0.91%(质量分数)提高到 7.60%(质量分数),已超过美国能源车用储氢系统的标准。本研究表明碳纳米管的微观结构组织对其储氢性能有至关重要的影响。
An optimal microstructure of carbon nanotubes was obtained by three-step oxidation of HNO3/HCl-HNO3/HF-oxidation by air on the basis of theories of micropore filling and adsorption. Treated with this process, most of the enclosed hemi-spherical fullerenes at two ends of tubes were opened, the average interior diameter expanded from 5 nm to 25 nm, sidewall became much thinner, agglomerated bundles of CNTs dissociated into isolated ones, specific surface area was heightened by approximately 2.5 times (from 180.5 m2/g to 649.5 m2/g) and hydrogen storage capacity was increased by approximately 7 times (from 0.91 wt% to 7.60 wt%) which have exceeded DOE energy standard of vehicular hydrogen storage. Our study shows forcefully that it is crucial for microstructure of CNTs to their properties of storing hydrogen.
出处
《功能材料》
EI
CAS
CSCD
北大核心
2005年第2期291-294,共4页
Journal of Functional Materials
基金
国防基础研究资助项目(J1500E002)
关键词
碳纳米管
储氢
改性
微观结构
Carbon nanotubes
Chemical modification
Hydrogen fuels
Microstructure
Oxidation
Thermogravimetric analysis
Transmission electron microscopy
