Using Monte Carlo simulations (MCS) in combination with an analytical model for the metal-metal interaction with the parameters based on density functional theory (DFT), Zhu, Qi, Yuan, and Gao predicted that the Ostwald ripening of Au nanoparticles on TiO 2 occurs primarily via the detachment and attachment of Au dimers. I show that this and some other predictions are not properly validated because the parameters employed in the analytical model in order to describe the Au-Au interaction are in fact inconsistent both with DFT and experimental thermodynamical data.