Carbon monoxide adsorption on the single-walled carbon nanotube supported gold–silver nanoalloys

Abstract

We have investigated CO adsorption on the (Ag–Au)_N nanoalloys supported on carbon nanotubes (CNTs) at different temperatures and pressures via MD simulation. We have studied many of the possible effects; the effects of the nanoalloy size, nanocluster mole fraction, CNT diameter, and CNT chirality, and the effect of the support on the thermodynamic, structural, and dynamic properties of the CO adsorption on the supported nanoalloys. Our results indicated that the nanoalloy size and mole fraction have considerable influences on the adsorption phenomena. The smaller nanoalloys with more Au mole fraction have more saturation coverage than the bigger nanoalloys with less gold atoms. Our simulations also indicated that the CNT diameter has significant influences on the CO adsorption. The coverage on the nanoalloy surface increases upon decreasing the diameter of the nanotube. The calculations also showed that there is a small difference between the results of the two CNT configurations. The saturation value of coverage is a little more for the nanoalloy deposited on the zigzag CNT than the armchair one. It is also shown that the enthalpy and entropy changes of adsorption, radial distribution functions, and self-diffusion coefficients respond to the different effects in consistent with the adsorption isotherms.