Electrocatalytic Oxidation of HCOOH on Pt(331)/Sb Electrode

Single crystal planes provide surface models of well defined atomic arrangement. Using the method of UPD and irreversibly adsorption (IRA) to modify electrode with adatoms can change the composition,the symmetry of atomic arrangement and the electronic structure of electrode surface^1]. We have studied in this paper the electrochemical behavior of irreversibly adsorbed antimony on Pt(331) (Pt(331)/Sb) and HCOOH oxidation on R(331)/Sb. The result demonstrated that the IRD Sb adatoms on Pt (331) was stable at potentials below 0.30 V (SCE). We illustrated that various coverage of Sb_ad can be easily obtained by controlling the number of potential cycling and the upper limit of potential scan (Eu). The coadsorption of Sb with H on Pt(331) surface was characterized by relation between the coverage of Sb (θ_Sb) and that of H_ad (θ_H). Two domains were determined:(1) when θ_Sb is small than 0.10, dramatic decrease of θ_H with θ_Sb is manifested, meaning that hydrogen adsorption can be inhibited significantly by a small quantity of Sb_ad; (2) when θ_Sb is large than 0.10, θ_H maintains almost a constant value near 0.025.