Computational study of specific ion effect on the graphene oxide surface

Sara Matić1,2 , Babak Minofar2,3 and David Řeha2,3

1Faculty of Science, University of Zagreb, Zagreb, Croatia

2Center for Nanobiology and Structural Biology, Institute of Microbiology, Academy of Sciences of the Czech Republic, Zámek 136, Nové Hrady, Czech Republic

3Institute of Physics and Biophysics, Faculty of Science, University of South Bohemia, České Budějovice, Czech Republic


Graphene oxide (GO), which is a monolayer of graphene with various oxidized groups, has wide application in materials technology, biomedicine, catalysis, as well as a surfactant. Due to it's amphiphilic nature GO can be dispersed in both water and organic solvents. This makes it a suitable carrier for isolation of hazardous chemicals such as dyes from industial waste water. The efficiency of graphene oxide as a carrier depends on pH [1] as well as the presence of different salts in solution [2].

MD simulations enable to understand the pH dependece of the interactions of different ions with GO surface on molecular level. The influence of ions to the surface charge of GO has been quantified by radial distribution function, which calculates the distribution of ions around a single molecule of GO. The observed interaction modes of ions with the surface of GO support experimental results from zeta potential measurements of graphene oxide in different salt solutions, as well as the efficiency in extraction of methyl blue from aqueous solutions [2].

1.         Sharma P., Borah D.J. and Das M.R., Graphene oxide nanosheets at the water-organic solvent interface: utilization in one-pot adsorption and reactive extraction of dye molecules. Chemphyschem., 2014, 15(18), 4019-25.

2.         Borthakur P., Boruah P.K., Hussaina N., Sharma B., Das M.R., Matić S., Řeha D. and Minofar B., An experimental and theoretical study of specific ion effect on the graphene oxide surface and investigation of their influence in reactive extraction of model dye molecule at water/organic interface. unpublished data