▎ 摘　　要

The atomic behavior of epoxy groups on a graphene oxide sheet was observed during high thermal heat annealing using a reactive force-field based on molecular dynamics simulations. We found the oxygen-containing functional groups interplay with each other and desorbed from the graphene oxide sheet by a form of O-2 gas if they were initially in close distance. Through comparing reduction results of graphene oxide with different densities of the nearest neighboring epoxy pairs, we confirmed that the amount of released O-2 gas has a clear tendency to increase with a higher density of epoxy pairs in close distance on a graphene oxide sheet. (C) 2012 The Japan Society of Applied Physics