Molecular dynamics of reactions between (4,0) zigzag carbon nanotube and hydrogen peroxide under extreme conditions

ABSTRACT

Single-wall carbon nanotubes (CNTs) have been suggested as potential materials for use in next-generation gas sensors. The sidewall functionalisation of CNTs facilitates gas molecule adsorption. In this study, density functional theory (DFT)-based ab initio molecular dynamics simulations are performed for a periodic zigzag single-wall (4,0) CNT surrounded by a monolayer of hydrogen peroxide molecules in an attempt to find conditions that favour sidewall functionalisation. The dependency of dynamics on charge states of the system is examined. It is found negative charges favour reactions that result in the functionalisation of the CNT. First principles molecular dynamics of defect formation yields chemically reasonable structure of stable defects, which can be reproduced in CNTs of any diameter and chirality. The explored hydroxyl and hydroperoxyl defects increase conductivity in a large diameter (10,0) CNT, while decrease conductivities in a small diameter (4,0) CNT.

KEYWORDS:

• Carbon nanotubes
• ab initio molecular dynamics
• hydrogen peroxide
• sensors
• conductivity

Acknowledgments

Authors thank Svetlana Kilina, Andrei Kryjevski, Sergei Tretiak for inspiring discussions. The authors would like to thank Douglas Jennewein for support and maintaining the High-Performance Computing system at the University of South Dakota. Gratefulness is also extended to Dane Hogoboom, Aaron Forde, Jon Vogel, Deyan Mikhaylov, and Bakhtyor Rasulev for collective discussion and editing.

Disclosure statement

No potential conflict of interest was reported by the authors.

Additional information

Funding

This research has been supported by Division of Chemistry [NSF CHE-1413614], [CHE-1460872]; DOE BES NERSC [allocation awards #91202 and #31857 "Computational Modeling of Photo-Catalysis and Photo-Induced Charge Transfer Dynamics on Surfaces"]; Office of Science of the DOE [contract number DE-AC02-05CH11231].