Agglomerated CNTs synthesized in a fluidized bed reactor: Agglomerate structure and formation mechanism

被引：131

作者：

Hao, Y ^{[1
]}

Zhang, QF ^{[1
]}

Wei, F ^{[1
]}

Qian, WZ ^{[1
]}

Luo, GH ^{[1
]}

机构：

[1] Tsinghua Univ, Dept Chem Engn, Beijing 100084, Peoples R China

来源：

CARBON | 2003年 / 41卷 / 14期

关键词：

carbon nanotubes; chemical vapor deposition; electron microscopy; Raman spectroscopy;

D O I：

10.1016/S0008-6223(03)00425-1

中图分类号：

O64 [物理化学（理论化学）、化学物理学];

学科分类号：

070304 ; 081704 ;

摘要：

Agglomerated carbon nanotubes (CNTs) were synthesized by catalytic pyrolysis of propylene on Fe/Mo/Al2O3 catalysts in a nano-agglomerate fluidized-bed reactor (NAFBR) of 196 mm I.D. The macroscopic properties and microstructure of the CNTs and their evolution were systematically characterized by high resolution transmission electron microscopy, energy dispersive X-ray spectroscopy and Raman spectroscopy. The CNTs from the NAFBR are sub-agglomerates entangled with each other. Their formation involves the initial fragmentation of the catalyst support, sub-agglomerate formation and expansion of the agglomerates due to CNT growth. When the structure of the catalysts is destroyed, the release of stress inside the catalyst particles will result in structural defects in the CNT shells. More perfect CNTs are obtained in fully developed agglomerates. A model is proposed to explain the process of agglomerate formation and based on its formation mechanism, an approach to control CNT quality in an NAFBR is proposed. (C) 2003 Elsevier Ltd. All rights reserved.

引用

页码：2855 / 2863

页数：9

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