文献类型：期刊文献

英文题名：Importance of oxygen in single-walled carbon nanotube growth: Insights from QM/MD simulations

作者：Wang, Ying[1];Song, Wei[2];Jiao, Menggai[1,3];Wu, Zhijian[1];Irle, Stephan[4,5]

第一作者：Wang, Ying

通讯作者：Wang, Y[1]

机构：[1]Chinese Acad Sci, Changchun Inst Appl Chem, State Key Lab Rare Earth Resource Utilizat, Changchun 130022, Peoples R China;[2]Xinxiang Univ, Phys & Elect Engn Dept, Xinxiang 453003, Peoples R China;[3]Nankai Univ, Tianjin Key Lab Met & Mol Based Mat Chem, Collaborat Innovat Ctr Chem Sci & Engn Tianjin,Na, Computat Ctr Mol Sci,Inst New Energy Mat Chem,Sch, Tianjin 300350, Peoples R China;[4]Nagoya Univ, Grad Sch Sci, Inst Transformat Biomol WPI ITbM, Nagoya, Aichi 4648602, Japan;[5]Nagoya Univ, Grad Sch Sci, Dept Chem, Nagoya, Aichi 4648602, Japan

第一机构：Chinese Acad Sci, Changchun Inst Appl Chem, State Key Lab Rare Earth Resource Utilizat, Changchun 130022, Peoples R China

通讯机构：[1]corresponding author), Chinese Acad Sci, Changchun Inst Appl Chem, State Key Lab Rare Earth Resource Utilizat, Changchun 130022, Peoples R China.

年份：2017

卷号：121

起止页码：292-300

外文期刊名：CARBON

收录：;EI(收录号：20172403752734);Scopus(收录号：2-s2.0-85020242238);WOS:【SCI-EXPANDED(收录号:WOS:000405294400033)】；

基金：We thank Dr. Benji Maruyama for the helpful discussions. This work is supported by the National Natural Science Foundation of China (21503210, 21521092, 21673220), Jilin Province Natural Science Foundation (20150101012JC) and Special Program for Applied Research on Super Computation of the NSFC-Guangdong Joint Fund (the second phase). Part of the computational time is supported by the Performance Computing Center of Jilin University and Changchun Normal University.

语种：英文

外文关键词：Atoms - Chemical bonds - Electronegativity - Iron - Molecular dynamics - Molecular oxygen - Nanocatalysts - Nanotubes - Quantum chemistry - Reduction - Synthesis (chemical)

摘要：Quantum chemical molecular dynamics simulations based on the density-functional tight-binding (DFTB) method were performed to investigate the role of oxygen in single-walled carbon nanotube (SWCNT) growth process. We found that a suitable content of oxygen in an iron nano-catalyst particle can reduce the internal thermal mobility of Fe atoms in catalyst due to the formation of strong Fe-eO bonds. These strong FeeO bonds also cause reduction of the iron nano-catalyst particle diameter and hence accelerate the collisions of carbon atoms on the catalyst particles. Contrarily, the high electronegativity of oxygen will induce positive charges on the Fe surface and consequently slow down the thermal mobility of adsorbed carbon atoms, causing a reduction of the nucleation rate. By tuning these two opposing factors with the oxygen contents of the iron nanoparticles, potentially highly efficient syntheses of SWCNT including diameter control can be carried out. The current results indicated that in our simulations the optimum ratio of iron and oxygen was 6:1. The observed reduced iron mobility may have implications for Ostwald ripening and for the control of the catalyst shape. (C) 2017 Elsevier Ltd. All rights reserved.