Interaction of Hydrogen with Au Modified by Pd and Rh in View of Electrochemical Applications

Abstract

Hydrogen interaction with bimetallic Au(Pd) and Au(Rh) systems are studied with the density functional theory (DFT)-based periodic approach. Several bimetallic configurations with varying concentrations of Pd and Rh atoms in the under layer of a gold surface(111) were considered. The reactivity of the doped Au(111) toward hydrogen adsorption and absorption was related to the property modifications induced by the presence of metal dopants. DFT-computed quantities, such as the energy stability, the inter-atomic and inter-slab binding energies between gold and dopants, and the charge density were used to infer the similarities and differences between both Pd and Rh dopants in these model alloys. The hydrogen penetration into the surface is favored in the bimetallic slab configurations. The underlayer dopants affect the reactivity of the surface gold toward hydrogen adsorption in the systems with a dopant underlayer, covered by absorbed hydrogen up to a monolayer. This indicates a possibility to tune the gold surface properties of bimetallic electrodes by modulating the degree of hydrogen coverage of the inner dopant layer(s).

Understanding the structure and reactivity of NiCu nanoparticles: an atomistic model

“…Hence, an improvement of the electrocatalytic properties is required. Bimetallic materials have been explored to tune the chemical properties of the electrocatalysts to modify their activity for the reaction [13,14,15,16,17,18]. In this context, Cu seems an interesting choice to combine with Ni due to costs, corrosion stability in alkaline electrolytes and a weaker hydrogen adsorption (respect with Ni) [19].…”

Special Issue “50th Anniversary of the Kohn–Sham Theory—Advances in Density Functional Theory”

“…Juarez et al [15] present simulations for the hydrogen interaction with bimetallic Au(Pd) and Au(Rh) systems with a DFT-based periodic approach. The reactivity of an Au surface towards hydrogen was related to the presence of dopants (Pd or Rh), showing both similarities and differences between them.…”

Mapping surface segregation of single-atom Pt dispersed in M surfaces (M = Cu, Ag, Au, Ni, Pd, Co, Rh and Ir) under hydrogen pressure at various temperatures

“…In other word, depending on the affinity of the metal in the surface with the interacting gas, surface or bulk segregation may increase. Although, metal segregation has been commonly observed in bimetallic nanoparticles under reaction conditions [18][19][20][21][22], the segregation and the stability of the isolated atoms in the SAAs have been rarely studied [23]. Considering Pt, in spite of the large number of works devoted to the single-atom Pt dispersed in various surface types, the study of its stability under gas atmosphere and reaction temperature has never been undertaken.…”