Carbon anthraquinone-modified

Salimi, A., Banks, C.E., and Compton, R.G. (2003). Ultrasonic effects on the electroreduction of oxygen at a glassy carbon anthraquinone-modified electrode. The Koutecky-Levich equation applied to insonated electrocatalytic reactions. Phys. Chem. Chem. Phys., 5, 3988-93. 

Pognon, G., T. Brousse, L. Demarconnay, D. Belanger. 2011. Performance and stability of electrochemical capacitor based on anthraquinone modified activated carbon. Journal of Power Sources 196 4117-4122. 

Algharaibeh, Z., X. R. Liu, and P. G. Pickup. 2009. An asymmetric anthraquinone-modified carbon/ruthenium oxide supercapacitor. Journal of Power Sources 187 640-643. 

R.C., and Pal, R. (2013) Cyclic voltammetric investigation of caffeine at anthraquinone modified carbon paste electrode. International Journal of Electrochemistry,... 

Sarapuu A, Vaik K, Schiffrin DJ, Tammeveski K. Electrochemical reduction of oxygen on anthraquinone modified glassy carbon electrodes in alkaline solution. J Electroanal Chem 2003 541 23-9. 

Salimi A, Eshghi H, Sharghi H, Golabi SM, Shamsipur M. Electrocataljrtic reduction of dioxygen at the surface of glassy carbon electrodes modified by some anthraquinone substituted podands. Electroanalysis 1999 11 114—9. 

Valarselvan S, Manisankar P (2011) Electrocatalytic reduction of oxygen at glassy carbon electrode modified by polypyrrole/anthraquinones composite film in various pH media. Electrochim Acta 56(20) 6945-6953... 

Kalinathan K, DesRoches DP, Liu X, Pickup PG (2008) Anthraquinone modified carbon fabric supercapacitors with improved energy and power densities. J Power Sources 181 182-... 

The surface chemical effects of interest do not go as far as those induced in (extensively) modified carbon electrodes [248], e.g., by pyrolyzed phthalocyanines or macrocycles [249-255], by anthraquinone or its derivatives [126,247,256-259], or by aryl groups [125], or those of stable and efficient sonoelectrocatalysts by modifying GC electrodes with 9,10-phenanthraquinone or 1,2-naphthoquinone [260], Instead, it is explored here whether and how a seemingly simple but crucial issue has been addressed or resolved what makes 02 adsorption in ORR nondissociative The isotopic labeling evidence for this experimental fact has been presented half a century ago [261], and it has not been challenged [262], The implication, based on the equally noncontrover-sial literature that 02 chemisorption on carbons (even at room temperature) is dissociative, is summarized below ... 

Chen and coworkers published a formal [3 + 3]-type reaction to give highly substituted cyclohexenes 8. This domino process consists of an allylic-allylic alkylation of an a,a-dicyanoalkene derived from 1-indanone and Morita-Baylis-Hillman carbonates, following an intramolecular Michael addition, by employing dual orga-nocatalysis of commercially available modified cinchona alkaloid (DHQD)2AQN If (hydroquinidine (anthraquinone-l,4-diyl) diether) and (S)-BINOL. The cyclic adducts... 

Substituted anthraquinones. In the latter figure, 9>5% 2-propanol in carbon dioxide as the mobile phase results in a separation very similar to that with 5.51 2-methoxyethanol in carbon dioxide. In both cases 1,8-dlhydroxyanthraquinone elutes with and right after anthraquinone so those components are not separated, even at much lower modifier concentrations the retention times of anthraquinone and 1,8-dihydroxyanthraquinone increase together with the tailing of the 1,8-dihydroxyanthra-qulnone becoming more and more pronounced as the modifier concentration is decreased. However, with chloroform as the modifier, those two components are significantly split apart, with... 

The following asymmetrical PsC capacitor was studied as a typical example of a redox capacitor. 1,2-dihydroxybenzene (DHB also referred to as o-benzoquinone and catechol) obtained by modification of a carbon electrode was used in it as a positive electrode. The negative electrode used was an anthraquinone (AQ)-modified carbon electrode (Algharaibeh and Pickup, 2011). 

A Spectracarb 2225 carbon fabric (Engineered Fibres Technologies) was used as a basis for the synthesis of an AQ-modified carbon cloth (C-AQ) electrode. This cloth was immersed into the salt of anthraquinone-1-diazonium chloride 0.5 ZnCl2 in acetone. Then, water and 50 wt% hypophosphorous acid were added. Then, the thus-modified cloth was washed by deionized water and dried at 110°C for 20 min. 

As mentioned above, the pretreatment of the carbon electrode surface can significantly affect its ORR activity, and even alter the ORR mechanism. Actually, the carbon surface can also be modified by some monolayer substances such as anthraquinones (AQ), and transition metal macrocycle complexes. Due to the conjugate structures of these molecules, they can irreversibly adsorb on the carbon surface to form monolayers that could serve as an electrocatalyst for ORR. This kind of electrode structure can be used to evaluate the electrocatalyst s ORR activity, particularly in acidic solution. 

In all its forms, the surface of carbon has oxygenated functional groups and these have been used as the starting point for the covalent bonding of functional groups to the surface. Moreover, in order to enhance the coverage by the functional groups, it has become common to preoxidize the surface by either an anodic treatment or the use of a chemical oxidant. While the properties of these modified surfaces are more suited to sensors, such modifications have been explored for effluent treatment applications. For example, an oxidative treatment of carbon felt was found to enhance the rate of destruction of 4-nitrophenol by an electro-Fenton approach [109] while chemical modification with hydrazine [110] and an anthraquinone polymer [111] has also been reported to increase the efficiency of electro-Fenton treatment. 

In 2009, Chen et al. reported the first highly enantioselective allylic-allylic alkylation of a,a-dicyanoalkenes with Morita-Baylis-Hillman carbonates by dual organocatalysis of commercially available modified cinchona alkaloids and S)-BINOL. Excellent stereoselectivities were achieved for a broad range of substrates by using hydroquinidine (anthraquinone-l,4-diyl) diether ((DHQD)2AQN) as the cinchona alkaloid. Indeed, in all the cases studied, only one diastereomer was isolated with both excellent enantioselectivity and yield, as shown in Scheme 5.9. 

Maia G, Maschion FC, Tanimoto ST, Vaik K, Miieoig U, Tammeveski K (2007) Attachment of anthraquinone derivatives to glassy carbon and the electrocatalytic behavior oft he modified electrodes toward oxygen reduction. J Solid State Electrochem 11 1411-1420... 

Manisankar P, Gomathi A (2005) Electrocatalytic reductimi of dioxygen at the surface of carbon paste electrodes modified with 9,10-anthraquinone derivatives and dyes. Etectroanal-ysis 17(12) 1051-1057. doi 10.1002/elan.200403213... 

Tiwari 1, Singh M, Gupta M, Aggarwal SK (2012) Electroanalytical properties and appUcation of anthraquinone derivative-functionalized multiwalled carbon nanotubes nanowires modified glassy carbon electrode in the determination of dissolved oxygtai. Mater Res Bull 47 (7) 1697-1703. doi 10.1016/j.materresbull.2012.03.031... 

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