have studied the methanol dissociation kinetics on Pt(111) surface by using PBE and optB86b-vdW methods. It has been found that without any dispersion interactions, methanol tends to desorb from the surface, whereas the inclusion of dispersion effects predicts a low activation barrier of 0.18 eV for the C-H dissociation pathway in agreement with experimental observation. Hence, a scrutinization of dispersion corrected DFT methods subjected to the information about catalyst system, reactive intermediates and reaction pathways is requisite for accurate prediction of catalytically relevant parameters within the DFT framework.