Vinsamlegast notið þetta auðkenni þegar þið vitnið til verksins eða tengið í það: http://hdl.handle.net/1946/12107
DFT study of hydrogen adsorption and desorption at Pt edges and terraces for micro-facets of varying sizes
The interaction of hydrogen with edges and terraces of Pt surfaces was studied using density functional theory (DFT) calculations. Length of the (111) micro-facets was varied from 1 to 11 rows of Pt atoms in order to see how the electronic structure of the Pt surface affect the interaction strength between Pt and H. By this modeling, we want to investigate where hydrogen adsorbs and desorbs from Pt nano-particles (NPs) as they become bigger. In all cases, the H starts to cover the edges of the NPs, then the terraces become covered with H, and last the terrace sites next to the edges are filled. We see remarkable small difference in electronic structure and H binding energy as the micro-facets become larger. Desorption energy of H2 from ridge sites is strongly varying with positions and numbers of the nearest H neighbors on the surface from 0.7 to 0.4 eV.