Interaction of H2 with gold–palladium binary clusters: Molecular and dissociative adsorption

A density functional theory study of adsorption and dissociation of H2 molecule on small PdnAgm (n + m ≤ 4) metal clusters

“…It is obvious from the gure that the dissociative adsorption increases the R ABL of the entire cluster, while, with exception in the case of Pd-Ag cluster, no signi cant change occurs upon the molecular adsorption indicating that the former type of adsorption weakens the atomic interactions in the cluster. These results are consistent with the suggestion by Zhao et.al that dissociative adsorption of hydrogen greatly changes the geometry of Au n Pd m cluster [27].…”

“…Isomer Pd 2 H 2 _c is less stable structure than the previous two structures and found to have a higher energy than the ground state by 1.501 eV. This structure involves molecular hydrogen adsorption on top of one Pd atom in line with the axis of Pd 2 dimer with Pd-H and H-H bond lengths of 1.681 Å and 0.870 Å which are close to ndings in other reports [14,22,27]. Similarly, H 2 prefers to molecularly adsorb on top of one Ag atom in line with the axis of Ag 2 dimer forming the ground state structure (Ag 2 H 2 _a) with Ag-Ag, Ag-H and H-H bond lengths of 2.573 Å, 2.519 Å and 0.751 Å respectively.…”

“…Therefore, electronic structure methods can be effectively employed to describe their interactions with metal surfaces and provide valuable insights into essential properties of hydrogen-metal systems such as surface reactivity, bond-making and bond-breaking behaviors [17]. In this regard, a number of theoretical studies have been carried out on the interactions between atomic or molecular hydrogen with pure and/or binary metal clusters [5,6,8,9,13,14,[18][19][20][21][22][23][24][25][26][27][28][29]. It has been largely proposed that the nature of the metallic components, geometry and size are crucial in controlling the adsorption and dissociation behaviors of hydrogen on the binary cluster surfaces.…”

Adsorption of CO, NO, and H2 on the PdnAu55–n Nanoclusters: A Density Functional Theory Investigation within the van der Waals D3 Corrections

“…From all possible TM combinations to build bimetallic nanoclusters, PdAu is particularly interesting because these elements are largely employed in catalytic applications − and, specifically, in the understanding of the adsorption process. − Consequently, (PdAu) 55 nanoclusters are promising candidates for study because this particle size allows to change the composition to obtain properties variability in the molecular adsorption process. − Several previous works have focused on the molecular adsorption study on (PdAu) 55 nanoclusters; for example, Cheng et al have studied (PdAu) 55 nanoclusters combining analytical potentials with the density functional theory (DFT) calculations, where they have studied PdAu nanoclusters in the oxidation of CO to CO 2 . They verified that the CO adsorption energies are substantially dependent on the local environment and on the composition of the nanoclusters.…”

Optical readout of hydrogen storage in films of Au and Pd

“…Based on thermodynamic arguments there is a possibility of H + or H + 2 species inside the metal [44,45] Earlier studies showed that upon hydrogenation of Pd there is heat generation, while for H 2 release an elevated temperature of > 150 • C is required [46]. It is noteworthy that recent density functional calculations [47] of H 2 interaction with Au:Pd binary clusters revealed that H 2 molecules donates electrons to metal clusters in molecular adsorption. Hydrogen enters interior of Pd with larger inner surface area.…”