Adsorption properties of CH3COOH on (6,0), (7,0), and (8,0) zigzag, and (4,4), and (5,5) armchair single-walled carbon nanotubes: A density functional study

The behaviour of CH3COOH molecule adsorbed on the external surface of H-capped (6,0), (7,0), and (8,0) zigzag, and (4,4), and (5,5) armchair single-walled carbon nanotubes was studied by using density functional calculations. Geometry optimizations were carried out at the B3LYP/6-31G∗∗ level of theory by using the Gaussian 03 suite of programs. We present the nature of the CH3COOH interaction in selected sites of the nanotubes. Adsorption energies corresponding to adsorption of the CH3COOH are calculated to be in the range 47–174kcalmol−1. The calculated adsorption energies for CH3COOH in H-down orientation are higher than those in O-down and C-down orientation for all of the configurations. More efficient adsorption energies cannot be achieved by increasing the nanotube diameter. We also provide the effects of CH3COOH adsorption on the electronic properties of the nanotubes.