(415f) More Accurate Depiction of Adsorption Energy on Transition Metals Using Work Function As One Additional Descriptor
Considering the fact that band hybridization and electron transfer could occur simultaneously when a molecule adsorbs to a TM surface, we propound that Eads contains a mixture of covalent and ionic contributions (i.e., Eads=Ecovalent + Eionic). The Ecovalent term would be describable using the Îµd parameter as it accounts for the band hybridization, whereas the Eionic term is determined by the charge transfer between TM and adsorbing molecules and thus would be related to the work function (W) parameter. Herein by taking both the ionic and covalent contributions into account, we suggest a new description model for Eads by dividing it into Ecovalent and Eionic components and adding W as one additional descriptor. We study the adsorption of O, OH, and OOH groups on TM surfaces using the new Eadsâ(Îµd, W) model with the explicit formula as Eads = f(Îµd, W) = z0+ a Ã Îµd + k Ã(W - W0)2 and achieve significantly better goodness of fit compared to the current EadsâÎµd model. We further demonstrate the new Eadsâ(Îµd, W) model can better predict activity property of TMs in oxygen reduction reaction (ORR) benefiting from a more accurate description of the oxygen binding energy (EO).