Hexanediamine Monolayer Electrografted at Glassy Carbon Electrodes Enhances Oxygen Reduction Reaction in Aqueous Neutral Media

Abstract

This study presents for the first time the electrocatalytic behaviour of hexanediamine (HDA) monolayer electrografted at glassy carbon (GC) electrodes that enhanced oxygen reduction reaction (ORR) in aqueous neutral media. HDA modified GC electrodes gave a higher current density than platinum bare electrodes based on the cyclic voltammograms (CV), although a ∼0.21 V vs. Ag/AgCl higher onset potential was observed at −0.1 mA cm-2. Electrochemical impedance spectra (EIS) showed that the electrocatalytic reaction on HDA monolayer film towards dissolved oxygen molecules is controlled by diffusion and charge transfer processes. From the scan rate studies and the Laviron equation, it was found that the ORR on this modified electrode proceeded via a fast four-electrons transfer.

Effect of Supporting Background Electrolytes on the Nanostructure Morphologies and Electrochemical Behaviors of Electrodeposited Gold Nanoparticles on Glassy Carbon Electrode Surfaces

“…The Bode plot can also be used to study and support the data obtained from the Nyquist plot. 31,32 Thus, to further study the electrochemical behaviors for each type of electrodes, EIS measurements were conducted in a 100 mM [Fe(CN) 6 ] 3−/4− solution and then compared with the bare GC and control electrodes. Figure 8A,B shows the Nyquist and Bode plots for the bare GC, control, and AuNPmodified GC electrodes.…”

“…Meanwhile, the Bode plot consists of the phase angle ( θ ) versus log frequency (Hz) (Figure B). The Bode plot can also be used to study and support the data obtained from the Nyquist plot. , …”

Engineering Co3O4/MnO2 nanocomposite materials for oxygen reduction electrocatalysis

“…Hence, the irreversible CV profile can be used to determine the transferred number of electrons into the reaction via Laviron method (equation 18) [73,74]:…”

Recent progress of conductive 3D-printed electrodes based upon polymers/carbon nanomaterials using a fused deposition modelling (FDM) method as emerging electrochemical sensing devices

“…However, there are still some potential approaches that could be attempted to improve the electrochemical performance of the 3D printed electrodes in the future. One of the methods is by electrochemically treating the 3D-printed carbon nanomaterial electrode in acetonitrile (ACN) with 0.1 M tetrabutylammonium tetrafluoroborate (TBATFB) using CV, cycled the potential between 0–2.0 V. 59 This will make the electrode surface rougher, thus, providing more electroactive sites available for redox reactions. In contrast, an enzyme solution could also be used to activate the 3D-printed carbon nanomaterial electrodes.…”

“…The 3D-printed carbon nanomaterial electrodes could also be used as electrode substrates for electrografting of primary amine linkers. These linkers play an essential role in obtaining stable monolayer electrografted primary amine linkers 59,71 that could be used to covalently attach redox probes, enzyme molecules or ssDNA molecules at the electrode surfaces. These modifications are very useful, especially for biosensors applications.…”