Nitrofluorene derivatives trapped within MWCNTs for electrocatalysis of NADH: Substituent effects on π-π stacking interaction strength

Abstract

We describe nanostructured electrode platforms composed of multiwalled carbon nanotube/glassy carbon electrodes (MWCNT/GCEs) with entrapped nitroaromatic compounds such as 2-nitrofluorene (2-NF), 2-nitro-9- fluorenone (2-NFN), 2,7-dinitrofluorene (2,7-NF) and 2,7-dinitro-9-fluorenone (2,7-NFN). All of the above ni- troaromatic compounds were tested as precursors for the production of redox mediator couples useful for NADH electrocatalysis. In this communication, we reveal the effect of the substituents on both the π-π stacking interaction strength and the electrocatalysis of NADH. The results show that the nitro group plays a triple role: it acts as a precursor of the mediator redox couple for NADH electrocatalysis; it increases the π-π stacking interaction with the electrode; and it acts as an electron acceptor substituent that promotes the electrocatalysis of NADH