Christian Punckt - Electrochemical Sensing of Nitric Oxide with Functionalized Graphene Electrodes

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      Publication Details (including relevant citation   information):

      Liu, Yifei M., Punckt, Christian, Pope, Michael A., Gelperin,   Alan, Aksay, Ilhan A. 5 12624-12630-

      Abstract: The intrinsic electrocatalytic   properties of functionalized graphene sheets (FGSs) in nitric   oxide (NO) sensing are determined by cyclic voltammetry with FGS   monolayer electrodes. The degrees of reduction and defectiveness   of the FGSs are varied by employing different heat treatments   during their fabrication. FGSs with intermediate degrees of   reduction and high Raman I-D to I-G peak ratios exhibit an NO   oxidation peak potential of 794 mV (vs 1 M Ag/AgCl), closely   matching values obtained with a platinized Pt control (791 mV) as   well as recent results from the literature on porous or   biofunctionalized electrodes. We show that the peak potential   obtained with FGS electrodes can be further reduced to 764 mV by   incorporation of electrode porosity using a drop-casting   approach, indicating a stronger apparent electrocatalytic effect   on porous FGS electrodes as compared to platinized Pt. Taking   into consideration effects of electrode Morphology, we thereby   demonstrate that FGSs are intrinsically as catalytic toward NO   oxidation as platinum. The lowered peak potential of porous FGS   electrodes is accompanied by a significant increase in peak   current, which we attribute either to pore depletion effects or   an amplification effect due to subsequent electrooxidation   reactions. Our results suggest that the development of sensor   electrodes with higher sensitivity and lower detection limits   should be feasible with FGSs.

      Address (URL): ://WOS:000328439600053