Interaction of trivalent arsenic on different topologies of Fe-doped graphene nanosheets at water environments: A computational study

In this work, a quantum chemical study was implemented to characterize the interaction of trivalent arsenic As (III) on the different structural topologies of Fe-doped graphene (FeG) at water environments. It was found that water molecules interact on FeG, but the stability of the FeG-As(III) complexes in water is thermodynamically preferred in all the topologies of FeG, with adsorption energies in the range of 1.1-1.5 eV. The FeG-As(III) complexes are of a coordinative covalent character, which remain bonded even in the presence of water coadsorption. Otherwise, hydroxide anions show a high stability onto FeG, larger than water and As(III); then, the recovery of FeG after adsorption could be straightforwardly reached by treatment at high pH solutions. Therefore, FeG could be implemented as a superior sorbent for a high removal efficiency of arsenic in aqueous environments. (C) 2019 Elsevier B.V. All rights reserved.