Alkaline media electrochemical oxidation

Guo X, Guo DJ, Qiu XP, Chen LQ, Zhu WT (2008) A simple one-step preparation of high utilization AuPt nanoparticles supported on MWCNTs for methanol oxidation in alkaline medium. Electrochem Commun 10(11) 1748-1751... 

Tusi MM, Polanco NSO, da Silva SG, Spinace EV, Neto AO (2011) The high activity of PtBi/ C electrocatalysts for ethanol electro-oxidation in alkaline medium. Electrochem Commun 13(2) 143-146... 

Pakalapati SNR, BN Popov, RE White (1996) Anodic oxidation of ethylenediaminetetraacetic acid on platinum electrode in alkaline medium. J Electrochem Soc 143 1636-1643. 

JusysZ. 1994. H/D substitution effect on formaldehyde oxidation rate at a copper anode in alkaline medium studied by differential electrochemical mass spectrometry. J Electroanal Chem 375 257-262. 

The electrocatal3rtic oxidation of sucrose has only been the subject of a few investigations. The chemical oxidation of sucrose was firstly mentioned in the works of Bresler (1) and Usch (2). Karabinos (3) analysed the oxidation products of fructose, glucose, glucono-y-lactone and sucrose in 0.5 M NaHCOa. The author concluded that the main reaction products were CO2 and H2O. Bockris et al. (4), investigated the electrochemical oxidation of different carbohydrates at platinum electrodes for their possible use in fuel cells. They noticed that the electroactivity was better in alkaline medium than in acidic medium, and that the reactivity of the molecule decreased with increasing molecular weights. 

The fact that the values of a are smaller in alkaline medium than in acidic medium (table 1) indicates that higher EOI and EOD values are generally obtained in alkaline medium for the electrochemical oxidation of substituted benzene derivatives. 

The imine formed on hydrolysis yields o-phenylenediamine and the corresponding carbonyl compound, and, depending on the pH of the medium, can also undergo further chemical and electrochemical reactions. By this reduction of carbohydrate derivatives of quinoxaline, the corresponding deoxy saccharides would be formed. For 1,2-dihydro-2,3-dimethylquinoxaline in an alkaline medium, the decrease in the height of wave i2 and the appearance of an anodic wave, ia, with increasing pH value prove that only its protonated form is reduced to the corresponding quinoxaline derivative, whereas its nonprotonated form is capable of oxidation to the initial 2,3-dimethylquinoxaline, as shown in Scheme 13. 

Post-column derivatlzation of reducing sugars with ethylene-diamine in a weakly alkaline medium at 150°C generates compounds detectable down to 1 pmol by electrochemical oxidation. This procedure was recommended over an earlier reaction involving 2-... 

To improve the electrocatalytic activity of platinum and palladium, the ethanol oxidation on different metal adatom-modified, alloyed, and oxide-promoted Pt- and Pd-based electrocatalysts has been investigated in alkaline media. Firstly, El-Shafei et al. [76] studied the electrocatalytic effect of some metal adatoms (Pb, Tl, Cd) on ethanol oxidation at a Pt electrode in alkaline medium. All three metal adatoms, particularly Pb and Tl, improved the EOR activity of ft. More recently, Pt-Ni nanoparticles, deposited on carbon nanofiber (CNE) network by an electrochemical deposition method at various cycle numbers such as 40, 60, and 80, have been tested as catalysts for ethanol oxidadmi in alkaline medium [77]. The Pt-Ni alloying nature and Ni to ft atomic ratio increased with increasing of cycle number. The performance of PtNi80/CNF for the ethanol electrooxidation was better than that of the pure Pt40/CNF, PtNi40/CNF, and PtNi60/CNF. 

Jafarian M, Moghaddam RB, Mahjani MG, Gobal F (2006) Electro-catalytic oxidation of methanol on a Ni-Cu alloy in alkaline medium. J Appl Electrochem 36(8) 913-918... 

Golikand AN, Raoof J, Baghayeri M, Asgari M, Irannejad L (2009) Nickel electrode modified by N,N-bis(salicylidene)phenylenediamine (Salophen) as a catalyst for methanol oxidation in alkaline medium. Russ J Electrochem 45(2) 192-198... 

Scientists investigated the electrochemical catalytical properties based on Pd/polyamide (Pd/PA6) electrospun nanofiber mats for the oxidation of ethanol in alkaline medium in which Pd/PA6 was directly used as electro-catalytic electrodes. 

Hydrogen oxidation reaction in a Pt-catalyzed gas diffusion electrode in alkaline medium. Journal of the Electrochemical Society, 152, E319-E327. 

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