ELECTROCHEMICAL, AUGER-ELECTRON SPECTROSCOPY AND LOW-ENERGY-ELECTRON DIFFRACTION STUDIES OF THE STABILITY OF THE AU(210) ELECTRODE SURFACE IN THE PRESENCE OF ADSORBED PYRIDINE

Electrochemistry, Auger electron spectroscopy (AES) and low energy ele ctron diffraction (LEED) have been employed to study the stability of the Au(210) electrode surface in the presence of adsorbed pyridine. Th e experiments have been performed in an ultrahigh vacuum (UHV)-electro chemistry apparatus that allows for a fast transfer of the sample betw een an UHV chamber equipped with LEED and AES equipment and an electro chemical chamber in which electrochemical experiments can be performed . The ''dry emersion'' technique has been employed to emerse the elect rode at a controlled potential and to transfer it into the UHV chamber for analysis of its surface composition using AES and its surface str ucture by LEED. Experiments performed in a weakly adsorbing electrolyt e and in 10(-3) M pyridine solution have shown that the Au(210) electr ode surface displays a remarkable stability at the metal-solution inte rface. Its surface structure is apparently unchanged when the electrod e charge density varies between -30 mu cm-2 and + 30 muC cm-2, both in a pure weakly adsorbing electrolyte and in the presence of the chemis orbed organic molecule.