Nanostructured electrodes and

A final topic to be discussed in this section is the direct injection of electrons into a liquid by the use of nanowires. The difference with the discharge processes described above for the point electrodes is twofold the use of nanostructured electrodes and the generation of solvated electrons, instead of the initiation of a discharge. Solvated electrons have a very short... 

D, or 2-D nanostructures. 2-D-based electrodes can be fabricated as homogeneous thin films or by an assembly of 0-D and 1-D nanostructures however, the film s thickness must be Umited to the nanoscale. 3-D electrodes can be similarly manufactured, but their thickness is not limited to nanolengths. Therefore, the assembly and synthesis of these nanostructures with multiple dimensions is common in electrochemistry. They are usually referred to as nanostructured electrodes and most of them are highly porous. 

In particular, we shall present results for the two electrochemical steps of the hydrogen reaction mechanism (Volmer and Heyrovsky) on plain and nanostructured electrodes, and illuminate the role of the reaction intermediate. We also discuss in detail the influence of the position of the metal d band and its interaction with the hydrogen orbital on the catalytic activity. 

We demonstrated that the morphology of nanostructures, electrochemical, and photoelectrochemical properties in the electrodes modified with nanodusters of Qo can be controlled by applying a strong magnetic field. The present study provides useful information for designing novel nanodevices whose photofunctions can be controlled by a magnetic field. 

Gooding JJ. 2005. Nanostructuring electrodes with carbon nanotubes A review on electrochemistry and applications for sensing. Electrochim Acta 50 3049-3060. 

Inspired by the amazing successes of surface scientists in nano structuring surfaces with the tip of an STM, albeit at UHV conditions and often at low temperatures [66-68], electrochemists began to use an STM or AFM as a tool for nanostructuring electrode surfaces, mostly by spatially confined metal deposition. Figure 5.15 summarizes the various routes, which are currently employed in the community for electrochemical nano structuring. In the following, we shall briefly address seven of them, and devote a separate chapter to the case sketched in... 

A conceptually different approach to nanostructuring electrode surfaces by tipgenerated metal clusters is sketched in Figure 5.15h. This approach, which facilitates a so-called jump-to-contact between tip and substrate for generating metal clusters, has been developed by our group and will be described in more detail in Section 5.4.3. 

Most of the work on nanostructuring electrode surfaces, which can be found in the literature, deals with the deposition of small metal clusters at predetermined positions. Over the years, we have developed a technique that is based on the jump-to-contact between tip and substrate [89] (Figure 5.15h) and that allows the formation of metal clusters in quick succession and without destroying the single crystallinity of the substrate. The principle behind this method is sketched in Figure 5.19 [90, 92] By applying an electrode potential to the STM tip that is slightly... 

A remaining crucial technological milestone to pass for an implanted device remains the stability of the biocatalytic fuel cell, which should be expressed in months or years rather than days or weeks. Recent reports on the use of BOD biocatalytic electrodes in serum have, for example, highlighted instabilities associated with the presence of 02, urate or metal ions [99, 100], and enzyme deactivation in its oxidized state [101]. Strategies to be considered include the use of new biocatalysts with improved thermal properties, or stability towards interferences and inhibitors, the use of nanostructured electrode surfaces and chemical coupling of films to such surfaces, to improve film stability, and the design of redox mediator libraries tailored towards both mediation and immobilization. 

Nanocarbon electrodes can also be prepared by utilizing the n electrons of nanocarbons and glassy carbon (GC) electrodes. For example, Cai et al. simply dropped an aqueous solution of RGO onto a cleaned GC electrode and allowed the solvent to dry. The n-7T interactions were suitable for the subsequent deposition of Pt-Au nanostructures via electrochemical reduction of varying ratios of PtCl and AuC14 [133]. 

The electrocatalytic activity of the nanostructured Au and AuPt catalysts for MOR reaction is also investigated. The CV curve of Au/C catalysts for methanol oxidation (0.5 M) in alkaline electrolyte (0.5 M KOH) showed an increase in the anodic current at 0.30 V which indicating the oxidation of methanol by the Au catalyst. In terms of peak potentials, the catalytic activity is comparable with those observed for Au nanoparticles directly assembled on GC electrode after electrochemical activation.We note however that measurement of the carbon-supported gold nanoparticle catalyst did not reveal any significant electrocatalytic activity for MOR in acidic electrolyte. The... 

Nanostructured Electrodes with Unique Properties for Biological and Other Applications... 

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