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Indexed by:期刊论文

Date of Publication:2013-07-01

Journal:CHEMOSPHERE

Included Journals:EI、SCIE

Volume:92

Issue:4

Page Number:429-434

ISSN No.:0045-6535

Key Words:Interaction; Low molecular weight organic acids; C-60; Molecular dynamics

Abstract:As an important part of dissolved organic matter (DOM), low molecular weight organic acids (LOAs) may play a key role in the process for DOM stabilizing carbon nanomaterials (e.g. C-60) suspensions in aquatic environment. In addition, both LOAs and C-60 have been detected in the troposphere and therefore have a chance to interact with each other in the gaseous phase. However, the mechanism for LOAs-C-60 interactions and their environmental implications need further investigations. In this study, molecular dynamics (MD) simulation was employed to investigate the interactions between both neutral and ionic LOAs with C-60 in vacuum and water. The results showed that the adsorptions of all LOAs on C-60 in energy are favorable, and the aromatic acids have stronger interactions with C-60 than the aliphatic acids in vacuum and water. The interaction energies (E-int) of the LOA anions with C-60 were weaker than those of their corresponding neutral LOA molecules. The models were also developed to predict and interpret Eint based on the results from MD simulations. Dispersion, induction and hydrophobic interactions were found to be the dominating factor in E-int. These findings indicate that cost-efficient MD simulation can be employed as an important tool to predict the adsorption behavior of LOAs on carbon nanomaterials. (c) 2013 Elsevier Ltd. All rights reserved.