Influence of the exchange–correlation potential on the description of the molecular mechanism of oxygen dissociation by Au nanoparticles

摘要

The effect of the exchange–correlation functional on the molecular mechanism of dioxygen dissociation by Au nanoparticles is investigated using three Au nanoparticles of increasing size (Au25, Au38 and Au79) and various exchange–correlation functionals (local density approach, PW91, PBE and RevPBE. The effect of the exchange–correlation functional on the calculated adsorption energies is quite large and systematic whereas the effect on the calculated energy barriers is much smaller. Implications for the molecular mechanism of O2 dissociation, involving a competition between desorption and dissociation, are analyzed and discussed in detail.