Single-crystal electrodes, macroscopic

Fig. 30. (a) Impedance spectrum measured with a Au microelectrode (Jme = 20 pm) on a Fe-doped SrTiOs single crystal. The arc represents the bulk properties. The rather high impedances are measured by means of a home-made impedance converter, (b) The applicability of microcontact impedance spectroscopy on SrTiC>3 is evidenced by the agreement of the bulk conductivity owk obtained by measurements with macroscopic electrodes and microelectrodes on a homogeneous crystal. 

In this paper, we advance a thermodynamic interpretation of the effect of chloride on copper surfaces in plating solutions. We have pursued this interpretation experimentally by observation of faceting on the sub-micron scale on low-index surfaces of copper single crystals. In the two sections that follow, relevant portions of the theory of equilibrium roughness and its relation to macroscopic faceting are presented. We consider how adsorbed chloride may stabilize the Cu(100) surface at equilibrium and relate this mechanism to simple models of thermal roughening. AFM experiments on copper plating on low-index copper crystal electrodes are then described and related to the theory. 

The macroscopic electrochemical experiments as well as the structural studies with molecular adlayers were performed on single crystal metal electrodes, such as Au hkl), Ag(hkl) and Cu(hkl). To describe our experimen-... 

In this chapter, we have attempted to show that in situ structural analysis techniques and traditional electrochemical measurements can be combined to obtain detailed insight into electrochemical reactions on single-crystal electrode surfaces. Thus, it is possible to establish a link between macroscopic electrochemical phenomena and atomic-scale surface structures. X-ray diffraction is a relatively new technique that takes advantage of the high brightness of synchrotron radiation sources to... 

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