Electrocatalysis Of Nanostructures: Monolayers Of Pd On Different Metal Electrodes M(111)

PAOLA QUAINO; ELISABETH SANTOS; WOLFGANG SCHMICKLER

Nice

Congreso; The 61st Annual Meeting of the International Society of Electrochemistry. Electrochemistry from Biology to Physics; 2010

International Society of Electrochemistry - ISE

Electrochemical nanostructures have gained a great interest in the last decadebecause of the large variation of their reactivity in comparison with bulk material. Anumber of groups worldwide investigate diverse nanostructures in order to improve theelectrocatalytic properties of electrode materials for several technological applications.However, the implementation of these nanomaterials is difficult due to the lack ofunderstanding of the fundamental aspects and mechanisms which determine theirstability, reactivity and dynamics.In this context, we have applied the electrocatalysis theory based on theSantos-Koper-Schmickler Hamiltonian [13] to investigate the reactivity ofnanostructures. Particularly in this contribution, we have systematically investigatedmonolayers of Pd at different substrates M(111), M=Au, Pt, Ru, Cu, Ni and calculatedby DFT the corresponding electronic density of states.Our results show that various effects contribute to determine the catalyticproperties: strain produced by changes in the distances to nearest neighbours plays animportant role, but it is not the only cause. Chemical interactions with the substratesalso produce modifications in the electronic properties and in consequence in thecatalytic activity. Of the investigated systems, Pd on Au(111) appears as the structureshowing the best catalytic effects, while monolayers on Cu(111) are less active thanbare surfaces of Pd(111) in accordance with experimental results.