| Density functional theory (DFT) calculations are performed to study the adsorption behavior of formaldehyde and methanol on the pristine as well as Al- or Si-decorated graphene oxide (GO). The most stable
adsorption configurations, adsorption energies, binding distances and net charge transfers are obtained
to understand the impacts of the these molecules on the electronic properties of the pristine or metaldecorated GO surface. The pristine GO exhibits a low sensitivity to both formaldehyde and methanol
molecules. However, it is found that the decoration of GO with a Al or Si atom enhances its tendency to
adsorb both the above gas molecules. Compared to formaldehyde, methanol is found to have a larger
adsorption energy over the decorated GOs, due to the more favorable orbital interaction as well as
electrostatic attraction in the resulted complexes. The amounts of charge transfer upon adsorption of
formaldehyde and methanol over the Al-decorated GO are larger than those of over the Si-decorated one.
Therefore, as a result of interaction with CH2O and CH3OH, the electronic properties of the Al-decorated
GO change significantly. |