Oxygen reduction catalysis at anthraquinone centres molecularly wired via carbon nanotubes

Abstract

Multi-walled carbon nanotubes (MWCNTs) have been chemically derivatised via the reduction of anthraquinone-1-diazonium chloride with hypophosphorous acid to attach 1-anthraquinonyl groups to the MWCNTs, most likely at edge plane like defects. The covalently attached quinone moiety attached to the nanotubes ('molecular wire') acts as an effective mediator for the electrocatalytic reduction of oxygen.

Comparison of the interactions of daunorubicin in a free form and attached to single-walled carbon nanotubes with model lipid membranes

“…The surface concentration calculated based on the cyclic voltammogram for the electrode modified with mixed DPPTE–SWCNTs-DNR monolayer is equal to 0.67 × 10 −10 mol/cm 2 , while the value obtained for DPPTE supported monolayer exposed to DNR solution is equal to 0.60 × 10 −10 mol/cm 2 as reported before [24]. Moreover, the values obtained for the mixed layer containing modified carbon nanotubes are comparable to the values reported for carbon nanotubes derivatized with antraquinone [35] and other types of electroactive species [36–37]. …”

Electroreduction of oxygen on multi-walled carbon nanotubes modified highly oriented pyrolytic graphite electrodes in alkaline solution

“…However, the disadvantage is that it is impossible to control the exact loading of the material attached. This method was used for immobilising chemically or electrochemically modified MWCNTs to pyrolytic graphite electrodes [19,20]. It was shown that the quinone moieties covalently attached to MWCNTs act as effective mediators for O 2 reduction [20].…”

Performance and stability of electrochemical capacitor based on anthraquinone modified activated carbon

“…Compton and coworkers introduced and optimized the modification of graphitic or glassy carbon powder by chemical reduction of 1-diazo-anthraquinone with H 3 PO 2 [27], and used their material to develop a pH probe [28]. AQ-modified electrodes were also investigated as electrocatalysts for the electrochemical reduction of oxygen [29,30] and also for electrochemical capacitor applications [31,32]. Pickup and coworkers have reported a 40% increase of capacitance for an elec- Experimental modification conditions, mass percentage of AQ in the material estimated by electrochemistry, contribution of each electrochemical processes of the system in the total capacitance (the gravimetric specific capacitance of each contribution is given for the total mass of the material).…”