Carbon-based electrodes

For example, the final heat treatment temperatures In the manufacture will produce different electrochemical properties, even with the same surface treatments (2-4) since the structure and electrical property of glassy carbon depends on the temperature, as Indicated by the single crystal TEM patterns and by measurement of temperature dependent conductivity (5-6). On the other hand. It Is also well established that the electrochemical properties of carbon-based electrodes are markedly affected by surface treatments. 

Centi, G. Perathoner, S., Problems and perspectives in nanostructured carbon-based electrodes for clean and sustainable energy. Catat. Today 2010,150 151-162. 

As in the case with PAFC s, voltage obtained from an AFC is affected by ohmic, activation, and concentration losses. Figure 4-7 presents data obtained in the 1960 s (18) which summarizes these effects, excluding ohmic losses, for a catalyzed reaction (0.5-2.0 mg noble metal/cm ) with carbon-based porous electrodes for H2 oxidation and O2 reduction in 9 N KOH at 55-60 C. The electrode technology was similar to that employed in the fabrication of PAFC electrodes. Performance of AFC s with carbon-based electrodes has not changed dramatically since these early results were obtained. 

A well-distributed deposition of Pt/C nanocatalyst and Nafion ionomer on bofh hydrophilic and hydrophobic carbon-based electrodes has been successfully obfained using a Pt/C concentration of 1.0 g/L, an electrical field of 300 V/cm, and a deposition time of 5 minutes [118]. The deposition of Pt/C nanocatalysts and Nafion solution via the electrophoretic process gives rise to higher deposition efficiency and a uniform distribution of catalyst and Nafion ionomer on the PEMFC electrodes. 

Louh, R. R, Huang, H., and Tsai, F. Novel deposition of Pt/C nanocatalysts and Nation solution on carbon-based electrodes via electrophoretic process for PEM fuel cells. Journal of Fuel Cell Science and Technology 2007 4 72-78. 

In many experiments a noncarbon-base anion-responsive electrode, silver-silver chloride, was employed. This electrode was selected for pairing with cation-responsive carbon-based electrodes because of its known properties and ease of preparation. 

Some indolylthiohydantoin derivatives that have aldose reductase inhibitory activity [75] were investigated electroanalytically by voltammetric determination. Based on this study, a simple, rapid, sensitive and validated voltammetric method was developed for the determination of the compounds that are readily oxidized at carbon-based electrodes. Oxidation of the indolic compounds occurs on the nitrogen atom in the indole ring of the molecule [162]. 

There are very few studies based on this approach, but it was demonstrated that using nanostructured carbon-based electrodes, it is possible to electrocatalytically reduce C02 in the gas phase using the protons flowing through a membrane [38], Long-chain hydrocarbons and alcohols up to C9 CIO are formed, with preferential formation of isopropanol using carbon-nanotube-based electrodes [14, 39]. Productivities are still limited, but these results demonstrate the concept of a new approach to recycle C02 back to fuels. 

Other types of carbon-based electrodes, such as activated carbon (Canizares et al. 1999), graphite particles (Piya-areetham et al. 2006), graphite Rashig rings (Ogutveren et al. 1999), and carbon black slurry (Boudenne et al. 1996 Boudenne and Cerclier 1999) have also been employed sometimes for the treatment of organic compounds. 

Iissens, G., Pieters, J., Verhaege, M., Pinoy, L. and Verstraete, W. (2003) Electrochemical degradation of surfactants by intermediates of water discharge at carbon-based electrodes. Electrochim. Acta 48, 1655-1663. 

The structure of the electrochemical double lay er in carbon based electrodes is closely related to the physical and chemical properties of the adjacent bulk material. Micropores... 

An approach focused on fabrication of nanostructured three-dimensional electrodes and introduction of surface modifications for tethering/retention in an optimal orientation of the MCOs to permit DET to the Tl site from the electrode shows great promise for the production of biocathode prototypes for application to EFCs. A systematic study of such electrodes modified with each of the MCOs available, reporting on their activity for ORR, using DET, under defined conditions of pH, mass transport, and temperature is not yet available, and would be a valuable contribution to advance the technological application of EFCs. A welcome recent focus is normalization of ORR, based on DET to Trametes versico/or adsorbed on porous carbon-based electrode materials, to electrode volume and to electrode... 

Ruiz, V., Blanco, C., Granda, M., Menendez, R., and Santamaria, R. 2008. Effect of the thermal treatment of carbon-based electrodes on the electrochemical performance of supercapacitors. Journal of Electroanalytical Chemistry 618, 17-23. 

The direct fixation of the biocatalyst to the sensitive surface of the transducer permits the omission of the inactive semipermeable membranes. However, the advantages of the membrane technology are also lost, such as the specificity of permselective layers and the possibility of affecting the dynamic range by variation of the diffusion resistance. Furthermore, the membrane technology has proved to be useful for reloading reusable sensors with enzyme. In contrast, direct enzyme fixation is mainly suited to disposable sensors. This is especially valid for carbon-based electrodes, metal thin layer electrodes printed on ceramic supports, and mass-produced optoelectronic sensors. Field effect transistors may also be envisaged as basic elements of disposable biosensors. 

Hart, J.P. Wring, J.P. (1991). Carbon-based electrodes and their application as electrochemical sensors for selected biomolecules. Anal. Proc. 28, 4-7... 

DEVELOPMENT OF A PESTICIDES BIOSENSOR USING CARBON-BASED ELECTRODE SYSTEMS... 

However, the electrical conductivity of the carbon nanomaterials is vulnerable to degradation due to the inefficient dispersion in a large-scale actuator. To this end, some metallic additives have been incorporated into the carbon-based electrode to enhance the electrical conductivity and actuation stability For instance, for the IPMC actuator where the reduced graphene oxide was used as electrode, the electrical conductivity of the electrodes could be efficiently improved after introduction of Ag nanoparticles (Fig. 8.2E) (Lu et al., 2013). As a result, both the actuation frequency and stability could be improved. Upon application of a low voltage of 1V, the actuator could be driven at a wide frequency range (0.01-10 Hz), and no obvious decrease in displacement was observed over 500 cycles of actuation. 

Pt-NPs have also been used as catalysts in gas sensors like nitric oxide (NO) sensor making use of the electrocatal3d ic effect in the oxidation of this specie [31]. In conjugation with carbon nanotubes (CNTs) and glutaraldehyde, Pt-NPs also allowed the development of a carbon-based electrode as a sensor for glucose, in a similar system as one of the reported H2O2 sensors [13]. 

Carbon and gold have a wide use in the technology of disposable sensors as electrodic materials [8]. Gold has been employed as electrodic material for the genosensors construction for years, and carbon is especially used due to its great superficial chemistry, its low background current, the wide potential window at which it is possible to be employed, its low cost, and its chemical passivity. Nevertheless, the electronic-transfer rate obtained with carbon-based electrodes is lower than that obtained with metallic electrodes [9]. 

Carbon-based electrodes are less sensitive to changes in DNA structure [4, 7, 8]. It was shown that G and A can be detected at... 

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