Electrochemical scanning tunneling

FIGURE 2-15 Design of a system for in-situ electrochemical scanning tunneling microscopy. 

We have found new CO-tolerant catalysts by alloying Pt with a second, nonprecious, metal (Pt-Fe, Pt-Co, Pt-Ni, etc.) [Fujino, 1996 Watanabe et al., 1999 Igarashi et al., 2001]. In this section, we demonstrate the properties of these new alloy catalysts together with Pt-Ru alloy, based on voltammetric measurements, electrochemical quartz crystal microbalance (EQCM), electrochemical scanning tunneling microscopy (EC-STM), in situ Fourier transform infrared (FTIR) spectroscopy, and X-ray photoelectron spectroscopy (XPS). 

As mentioned above, the methods based on detection of electrons or ions or probing the electrode surface by these particles are generally handicapped by the necessity to move the studied electrode into vacuum, i.e. to work ex-situ. There are, however, two important exceptions to this rule electrochemical mass spectrometry and electrochemical scanning tunnelling microscopy. 

Haiss W, Albrecht T, van Zalinge H, Higgins SJ, Bethell D, Hobenreich H, Schiffrin D J, Nichols RJ, Kuznetsov AM, Zhang J, Chi Q, Ulstrup J (2007) Single-molecule conductance of redox molecules in electrochemical scanning tunneling microscopy. J Phys Chem Bill 6703-6712... 

Electrochemical nanotechnologies using ultramicroelectrodes such as the tips of electrochemical scanning tunneling microscopes and related devices [446,447] are of special interest both, for conducting local electrosynthesis and for electrochemical modification. The tip nanotechnique in electrolyte solutions ensures the optimal level of surface purity, offers additional possibilities in governing the processes by varying the potentails of the tip electrode and the substrate, and may also be used for... 

Endres F, Freyland W (1998) Electrochemical scanning tunneling microscopy investigation of HOPG and silver electrodeposition on HOPG from the acid room temperature molten salt aluminium chloride - l-methyl-3-butylimidazolium chloride. J Phys Chem B 102 10229-10236... 

ZW Tian, ZD Fen, ZQ Tian, XD Zhuo, JQ Mu, CZ Li, HS Lin, B Ren, ZX Xie, WL Hu. Confined etchant layer technique for 2-dimensional lithography at high resolution using electrochemical scanning-tunneling-microscopy. Faraday Discuss 94 37-44, 1992. 

Summary, Scanning probe microscopy studies of electrodes chemically modified with electroactive transition metal complexes are described. Emphasis is placed on scanning tunneling microscopy and electrochemical scanning tunneling microscopy studies of their structure and dynamics of formation and on electrochemical force spectroscopy studies of their electrochemical potential dependent chemical properties. 

Molecular assemblies of functional (mostly N-heterocyclic) molecules on gold electrode surfaces studied by electrochemical scanning tunneling microscopy 06BCJ1167. 

Inaba M., Siroma Z., Kawatate Y., Funabiki A., Ogumi Z. Electrochemical scanning tunneling microscopy analysis of the surface reactions on graphite basal plane in ethylene carbonate-based solvents and propylene carbonate, J. Power Sources 1997, 68, 221-226. 

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