Molecular Dynamics Investigation on Hydrophilicity of Graphene OxideNanoparticles Grafted with Polysaccharides

The effects of grafting with cellulose (Cel) and chitosan (Ch) polysaccharides on the hydrophilicityof graphene oxide (GO) nanoparticles (NPs) were studied by molecular dynamics (MD)simulations. The total energy of NP/water systems decreased in the order of GO-Ch/waterGOCel/water > GO/water. This was attributed to the increase in hydrogen bonding between modifiedGOs over time, which reduced NP/water contacts and raised the total energy. Meanwhile, due to thehydrophilic and oxygen-containing groups of cellulose and chitosan, GO-Cel and GO-Ch showedhigher hydrogen bonding with water compared to GO. By converting chitosan to protonatedchitosan, the hydrophilicity and NP/water hydrogen bonding of GO-Ch was further increased. Thus,chitosan is preferred to improve the dispersion and hydrophilicity of GO in aqueous acidic media,while chitosan and cellulose exhibit comparable hydrophilicity in neutral water media.

کلیدواژه ها:

MD simulation ، graphene oxide ، grafting ، polysaccharide ، hydrophilicity ،