ELECTROCHEMICAL-BEHAVIOR OF IRREVERSIBLY ADSORBED TELLURIUM DOSED FROM SOLUTION ON PT(H, K, L) SINGLE-CRYSTAL ELECTRODES IN SULFURIC AND PERCHLORIC-ACID MEDIA

The voltammetric behaviour of irreversibly adsorbed tellurium on the t hree platinum basal planes has been studied. It has been shown that th ere exists a surface redox process on both Pt(111) and Pt(100) electro des which involves 4 electrons per adatom species. This process leads to the formation of oxygenated tellurium adspecies that remain stable on the surface. For both Pt(111) and Pt(100) electrodes adatom desorpt ion takes place at higher potential values than those corresponding to the surface redox process. However, in the case of Pt(110) electrodes the first oxidation process leads to the dissolution of the adlayer.