在Pt单壁碳纳米管复合材料中的溢出:形成稳定的C-H键
Ranadeep Bhowmick1, Srivats Rajasekaran, Daniel Friebel
1Department of Material Science and Engineering, Stanford University, Stanford, California 94305, USA.
Journal of the American Chemical Society
|March 25, 2011
概括
纳米颗粒通过溢出机制增强单壁碳纳米管 (SWNT) 中的吸收. 这一过程涉及化学吸收,形成共价C-H键并增加Pt-SWNT中的储能.
科学领域:
- 材料科学 材料科学 材料科学
- 纳米技术纳米技术
- 物理化学 物理化学
背景情况:
- 单壁碳纳米管 (SWNTs) 正在研究储存应用.
- (Pt) 纳米粒子是已知的解离的催化剂.
研究的目的:
- 为了研究纳米颗粒对SWNTs吸收的影响.
- 阐明金装饰的SWNT中储存的机制.
主要方法:
- 在暴露期间的现场电导度测量.
- 外置X射线光电子光谱 (XPS) 用于表面分析.
- 用喷射SWNT (Pt-SWNT) 和兰木尔-布洛杰特 (LB) 技术进行制备.
主要成果:
- 与纯SWNT相比,Pt-SWNT在暴露于气时的导电率下降得更快,这表明气溢出.
- XPS分析证实了通过化学吸收 (C-H键形成) 储存的情况.
- Pt-SWNT达到了16 ± 1.5分钟. %sp(3) 混合碳,相当于1.2重%的储能.
- 用LB准备的Pt-SWNT显示出最高的Pt/SWNT比率和优越的吸收.
结论:
- 纳米粒子通过溢出增强化学吸收机制促进SWNT中的吸收.
- 在Pt-SWNT中形成sp(3) 混合的碳原子是储存的关键.
- 优化Pt加载,特别是使用LB等方法,可以提高SWNT中的储能性能.
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