Gold surface, bisulfate anion

Our AES, LEED and CEELS data indicate that bisulfate anion is undergoing specific adsorption on these three (111) surfaces, but the coverage and the adsorption potential vary considerably among these substrates. For Au(l 11), the maximum is only 1/5 ML, both from the quantitative AES, chronocoulometric and radiochemical studies. For Pt(l 11) and Rh(l 11), the coverage is close to 1/3 ML. The latter coverage is typical of the Me(lll)(V3 X V3) R30° surface structure which we confirmed by electron diffraction. On gold, the (V3 x V3)-type structure is poorly developed and we... 

Herrero and Abruna [25] have also studied the kinetics and mechanism of Hg UPD on Au(lll) electrodes in the presence and absence of bisulfate, chloride, and acetate ions. In the absence of the interacting anions (in perchloric acid), the Hg UPD was significantly controlled by gold-mercury surface interactions. In sulfuric acid solutions, the kinetics of the initial and final stages of mercury deposi-tion/dissolution was altered. The presence of two well-ordered structures at potentials below and above mercury deposition led to the formation of two pairs of sharp spikes in cyclic voltammograms. In the chloride medium, the voltammetric profile exhibited two sharp peaks and thus it was very similar to that obtained in sulfuric acid solution. Neither nucleation, nor growth kinetics mechanism was found to be linked to the process of formation/disruption of the mercury chloride adlayer. The transients obviously deviated from the ideal Langmuir behavior. 

The electrosorption ofhisulfate on polyerystalline copper [145, 146] shows that it binds much more strongly than to gold. We may assume that the electrosorption potential of the bisulfate varies linearly with the amount of copper in the surface. Thus, guided by the work ofTrasatti on the influence of the anion on the potential of zero charge [147], we take... 

---