Density functional theory study on the adsorption and decomposition of CO on Ni- and Pt-Au(111) bimetallic surfaces

It is very important to elucidate how different structural units in a catalyst affect its performance in order to develop excellent heterogeneous catalysts. In this study, density functional theory (DFT) is used to investigate CO adsorption by transition metal (TM = Ni and Pt) monoatoms, dimers and trimers doped on Au substrates. The effects of different structural units on CO adsorption are analyzed. The results show that the Pt trimer has a stronger CO adsorption capacity than the other gold-based bimetallic catalysts. The effects of different Pt structural units on the C-O bond in CO molecules are investigated. An exploration of the transition states in CO decomposition on three different Pt-Au(111) surfaces leads to the conclusion that Pt aggregation weakens the C-O bond.