INDEX electrocatalysis

Chang SC, Leung LWH, Weaver MJ. 1990. Metal crystallinity effects in electrocatalysis as prohed hy real-time ETIR spectroscopy electrooxidation of formic acid, methanol, and ethanol on ordered low-index platinum surfaces. J Phys Chem 94 6013-6021. 

Markovic NM, Adzic RR, Cahan BD, Yeager EB. 1994. Structural effects in electrocatalysis— Oxygen reduction on platinum low-index single-crystal surfaces in perchloric-acid solutions. J Electroanal Chem 377 249-259. 

As mentioned in Section 5.1, adsorption of components of the electrolysed solution plays an essential role in electrode processes. Adsorption of reagents or products or of the intermediates of the electrode reaction or other components of the solution that do not participate directly in the electrode reaction can sometimes lead to acceleration of the electrode reaction or to a change in its mechanism. This phenomenon is termed electrocatalysis. It is typical of electrocatalytic electrode reactions that they depend strongly on the electrode material, on the composition of the electrode-solution interphase, and, in the case of single-crystal electrodes, on the crystallographic index of the face in contact with the solution. 

Identification of Peaks for Hydrogen Adsorption on the Disordered Low Index Planes. Besides the major objective for studying electrocatalysis on single crystal stepped surfaces mentioned above, these studies offer a wealth of information on the behaviour of polycrystalline surfaces, of preferentially oriented surfaces and, as we suggested recently (12), of disordered low-index surface. 

There are many substances which would appear to be good candidates for LC-EC from a thermodynamic point of view but which do not behave well due to kinetic limitations. Johnson and co-workers at Iowa State University used some fundamental ideas about electrocatalysis to revolutionize the determination of carbohydrates, nearly intractable substances which do not readily lend themselves to ultraviolet absorption (LC-UV), fluorescence (LC-F), or traditional DC amperometry (LC-EC) [2], At the time that this work began, the EC of carbohydrates was more or less relegated to refractive index detection (LC-RI) of microgram amounts. The importance of polysaccharides and glycoproteins, as well as traditional sugars, has focused a lot of attention on pulsed electrochemical detection (FED) methodology. The detection limits are not competitive with DC amperometry of more easily oxidized substances such as phenols and aromatic amines however, they are far superior to optical detection approaches. 

In electrocatalysis, the presence of surface defects is important to activate electron transfer in complex reactions. This is the consequence of the adsorbed species involved during the electro-catalytic process. Thus, Pt(l 10), the low Miller index plane, deserves special attention in theoretical studies. 

The electrocatalysis of ethanol oxidation using in situ FTIR spectroscopy was studied in several papers [76-80]. Some facts concerning the soluble reaction products at the low-index faces of Pt single-crystal... 

Using these nanomaterials, an interesting example in the field, is the coupling of copper nanowires (CuNWs) to ME. Indeed, CuNWs exhibit electrocatalysis toward carbohydrates becoming a selective detector with the expected enhanced sensitivity. This coupling has been explored for the fast and reliable analysis of monosaccharides in honey samples [56]. To this end, a representative group of nine honey samples were analyzed and the results were compared with those obtained by HPLC-RI (refractive index). ME-CuNWs approach... 

As a more recent example, microchip electrophoresis has been coupled to a copper-nanowire electrochemical detector that exhibited electrocatalysis toward carbohydrates, constituting a selective and sensitive detector that was applied in the fast and reliable analysis of monosaccharides in honey samples (Garcia and Escarpa, 2014). Glucose and fructose were separated in less than 250 s, the obtained results agreeing, with errors lower than 10%, with those obtained by high-pressure EC (HPLC)-refractive index. 

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