Rotating Disk Electrode Voltammetry Research Articles

Effect of prolonged electrode potential cycling on the conduction properties of poly(o-aminophenol) film electrodes

The aim of this work was to study the effect of prolonged potentiodynamic cycling (PPC) on the conducting properties of poly(oaminophenol) (POAP) film electrodes. PPC reduces strongly the electron transport rate at POAP films. This effect is called herein deactivation. Cyclic Voltammetry (CV), Rotating Disc Electrode Voltammetry (RDEV) and Electrochemical Impedance Spectroscopy (EIS) were employed in this study. The attenuation of the voltammetric response of the polymer with the increase in the number of oxidation-reduction cycles allowed one to define a degree of deactivation. RDEV and EIS were employed to obtain the dependence of some charge-transport parameters on the degree of deactivation of the polymer. RDEV data were interpreted in terms of the electron hopping model. Impedance spectra were analysed on the basis of a model which considers a protonation reaction coupled with a self-exchange process between oxidized and reduced sites. POAP films maintain their conducting properties almost unaltered for about 500 potential cycles at a scan rate of 0.010 Vs−1. However, a loss of conductivity was observed as the number of potential cycles was extended beyond 500.

A Study of the Charge Transport Process at Nickel Hydroxide-Gold Modified Electrodes employing Rotating Disc Electrode Voltammetry and Ac Impedance Measurements

The aim of the present work was study how the charge-transport process of a nickel hydroxide film electrochemically synthesized on a gold substrate is modified when the electrode is stored without use for long time. It was found that nickel hydroxide films deactivate under storage, that is, films become less conductive than immediately prepared ones (nondeactivated). This study was carried out in the context of the Rotating Disc Electrode Voltammetry (RDEV) and Electrochemical Impedance Spectroscopy (EIS) when the modified electrode contacts an electroactive solution and a redox reaction occurs at the Au−Ni(OH)2|ectrolyte interface. Variations of anodic limiting currents with the electrode rotation rate, for both nondeactivated and deactivated films in the presence of the electroactive solute deferasirox (4-(3,5-bis(2-hydroxyphenyl)-1,2,4-triazol-1-yl) benzoic acid) allowed one obtaining a charge transport rate across a nickel hydroxide film, which decreases with the increase of the storage time. Interpretation of impedance spectra obtained at potential values corresponding to the anodic limiting currents on the basis of an impedance model that considers an uniform and nonporous nickel hydroxide film deposited in a conductive substrate and no penetration of redox species (deferasirox) from the solution, allowed one obtaining different interfacial resistances and electron and ion diffusion coefficients for the Au−Ni(OH)2|ectrolyte system.

Applications of Convolution Voltammetry in Electroanalytical Chemistry

The robustness of convolution voltammetry for determining accurate values of the diffusivity (D), bulk concentration (C(b)), and stoichiometric number of electrons (n) has been demonstrated by applying the technique to a series of electrode reactions in molecular solvents and room temperature ionic liquids (RTILs). In acetonitrile, the relatively minor contribution of nonfaradaic current facilitates analysis with macrodisk electrodes, thus moderate scan rates can be used without the need to perform background subtraction to quantify the diffusivity of iodide [D = 1.75 (±0.02) × 10(-5) cm(2) s(-1)] in this solvent. In the RTIL 1-ethyl-3-methylimidazolium bis(trifluoromethanesulfonyl)imide, background subtraction is necessary at a macrodisk electrode but can be avoided at a microdisk electrode, thereby simplifying the analytical procedure and allowing the diffusivity of iodide [D = 2.70 (±0.03) × 10(-7) cm(2) s(-1)] to be quantified. Use of a convolutive procedure which simultaneously allows D and nC(b) values to be determined is also demonstrated. Three conditions under which a technique of this kind may be applied are explored and are related to electroactive species which display slow dissolution kinetics, undergo a single multielectron transfer step, or contain multiple noninteracting redox centers using ferrocene in an RTIL, 1,4-dinitro-2,3,5,6-tetramethylbenzene, and an alkynylruthenium trimer, respectively, as examples. The results highlight the advantages of convolution voltammetry over steady-state techniques such as rotating disk electrode voltammetry and microdisk electrode voltammetry, as it is not restricted by the mode of diffusion (planar or radial), hence removing limitations on solvent viscosity, electrode geometry, and voltammetric scan rate.

Preparation of MOF(Fe) and its catalytic activity for oxygen reduction reaction in an alkaline electrolyte

Effective bifunctional catalysts play a vital role in large-scale commercial applications of rechargeable lithium-air batteries. In this article, a metal-organic framework, MOF(Fe), was prepared by a hydrothermal process using ferric nitrate as the metal ion precursor and trimesic acid as an organic ligand. The structure of the MOF(Fe) was characterized by X-ray diffraction, N 2 adsorption-desorption, Transmission electron microscopy, Fourier transform infrared spectroscopy and Thermo-gravimetric analysis. The activity for the oxygen reduction reaction (ORR) and the kinetic behavior of the ORR using the MOF(Fe) were investigated by cyclic voltammetry and rotating disk electrode voltammetry, respectively, using an alkaline electrolyte. The characterization results showed that the MOF(Fe) was highly crystalline with abundant micropores, large specific surface area and high thermal stability. The MOF(Fe) exhibited excellent catalytic activity for the ORR. The ORR mechanism varies with the applied potentials. The ORR occurs through a two-electron pathway at potentials in the range of −0.30 to −0.50 V, but shifts to four-electron pathway with the potentials in the range −0.50 to −0.95 V. In addition, the MOF(Fe) shows excellent catalytic activity for the oxygen evolution reaction (OER) in an alkaline electrolyte. This work opens a new route for the development of effective non-precious metal catalysts based on MOFs for the ORR and OER. MOF(Fe) was synthesized by a hydrothermal method and shows excellent bifunctional catalytic activity for the oxygen evolution reaction (OER)and oxygen reduction reaction (ORR) in an alkaline electrolyte.

Effect of prolonged electrode potential cycling on the charge transport parameters of poly(o-aminophenol) films. A study employing rotating disc electrode voltammetry and surface resistance

The aim of this work was to study the effect of prolonged potentiodynamic cycling (PPC) on the conducting properties of poly(o-aminophenol) (POAP) film electrodes. Cyclic Voltammetry (CV), Rotating Disc Electrode Voltammetry (RDEV) and Surface Resistance (SR) were employed in this study. The attenuation of the voltammetric response of the polymer with the increase in the number of oxidation–reduction cycles allowed one to define a degree of deactivation. RDEV was employed to obtain the dependence of the electron diffusion coefficient on the degree of deactivation of the polymer. The slower electron transport with the increase in the degree of deactivation was attributed to the increase of the electron hopping distance between redox sites. The attenuation of the relative resistance changes (ΔR/R) of a gold film coated with a POAP film as the degree of deactivation increases was also associated to changes in the redox site configuration at the gold/POAP interface after PPC. POAP films maintain their conducting properties almost unaltered for about 500 potential cycles at a scan rate of 0.010Vs−1. However, a loss of conductivity was observed as the number of potential cycles was extended beyond 500.

One-pot synthesis of PtNi alloy nanoflowers supported on multi-walled carbon nanotubes with superior electrocatalytic activity for the oxygen reduction

Well-defined PtNi alloy nanoflowers supported on multi-walled carbon nanotubes (PtNi-H/MWCNTs) are successfully synthesized through a novel and potentially general one-pot reaction that exploits an in situ sacrificial template. The detailed morphology, composition, and structure of the PtNi alloy nanoflowers are investigated by transmission electron microscopy, energy-dispersive X-ray spectroscopy, nitrogen adsorption–desorption isotherms and X-ray diffraction. The results demonstrate that the PtNi-H/MWCNTs are highly porous. The electrocatalytic activity and stability of the PtNi-H/MWCNTs for the oxygen reduction reaction (ORR) are investigated by rotating disk electrode voltammetry in 0.1 mol L−1 HClO4 solution. The electrochemical tests indicated that PtNi-H/MWCNTs exhibited superior ORR activity along with satisfactory stability and methanol-tolerance under acidic conditions, which made them promising electrocatalysts.

Effect of Furfuryl Alcohol on Metal Organic Framework-based Fe/N/C Electrocatalysts for Polymer Electrolyte Membrane Fuel Cells

Fe/N/C electrocatalysts for the oxygen reduction reaction (ORR) in polymer electrolyte membrane fuel cells (PEMFCs) have been synthesized from iron acetate (FeIIAc), 1,10-phenanthroline (phen), furfuryl alcohol (FA) and a thermally-decomposable metal-organic framework (MOF). The catalyst precursors have been prepared according to two main synthesis schemes. In the first one, a nitrogen-doped carbon was first synthesized from the MOF impregnated with FA, and this carbon was subsequently used as a microporous support for FeIIAc and phen. In the second approach, the FA-impregnated MOF was used as a support for FeIIAc and phen. The catalyst precursors prepared from these two approaches were subjected to a first pyrolysis in Ar and to a second pyrolysis in NH3. The effect of the pyrolysis temperature in Ar and heating rate were investigated. The as-prepared electrocatalysts were characterized by transmission electron microscopy, N2 sorption analysis, as well as Mössbauer and X-ray absorption spectroscopies for the optimized catalysts. The electrochemical properties towards the ORR were investigated by rotating-disk electrode voltammetry and H2–O2 PEMFC tests.

Iron- and Nitrogen-Functionalized Graphene Nanosheet and Nanoshell Composites as a Highly Active Electrocatalyst for Oxygen Reduction Reaction

In this work, we develop a simple method to thermally synthesize a nonprecious metal-based nitrogen-doped graphene (NG) electrocatalyst using exfoliated graphene (Ex-G) and urea with varying amounts of iron (Fe) precursor. The morphology and structural features of the synthesized electrocatalyst (Fe-NG) were characterized by SEM and TEM, revealing the existence of graphitic nanoshells that potentially contribute to the ORR activity by providing a higher degree of edge plane exposure. The surface elemental composition of the catalyst was analyzed through XPS, which showed a high content of a total N species (∼8 at. %), indicative of the effective N-doping, present mostly in the form of pyridinic nitrogen groups. The oxygen reduction reaction (ORR) performance of the catalyst was evaluated by rotating disk electrode voltammetry in alkaline electrolyte and in a zinc-air battery cell. Fe-NG demonstrated high onset and half-wave potentials of −0.023 V (vs SCE) and −0.110 V (vs SCE), respectively. This excellen...

Non-Enzymatic Glucose Oxidation at Electrocatalytic Metal Oxide Films

The electro-oxidation of glucose at nickel hydroxide films is discussed. These films can be electrodeposited using a simple potential multi-cycling procedure. The resulting films exhibit a nanostructured surface morphology. Cyclic voltammetry, rotating-disk electrode voltammetry and electrochemical impedance spectroscopy have been used to elucidate the kinetics and mechanism of the oxidation of glucose. NiOOH is shown to be the active form of the nickel hydroxide layer and the impedance data indicates significant surface adsorption at these sites. Furthermore, mass-transport-corrected Tafel slopes of ca. 40 and 60 mV/dec were observed at low and high potentials respectively identifying a change in rate-control with increasing potential. Finally, we show using amperometric techniques that this simple modified electrode possesses excellent sensitivity for the oxidation of glucose, displaying current increases of ca. 3.7 mA mM−1 cm−2 with a limit of detection of the order of 2.0 μM glucose.

The effects of nicotine and tobacco particulate matter on dopamine uptake in the rat brain

Cigarette smoking is the leading cause of preventable death worldwide. Recently, tobacco extracts have been shown to have a different pharmacological profile to nicotine alone and there is increasing evidence of a role for non-nicotinic components of cigarette smoke in smoking addiction. Nicotine is known to affect the uptake of dopamine in the brain of laboratory animals, but studies in the literature are often contradictory and little is known of the effects on non-nicotinic tobacco components on dopamine uptake. This study has examined the acute and chronic effects of nicotine and a tobacco extract (TPM) on dopamine uptake by the dopamine and norepinephrine transporters (DAT and NET) ex vivo using rotating disk electrode voltammetry, and quantified DAT and NET protein and mRNA expression in key brain regions. Nicotine (0.35 mg/kg) significantly decreased DAT function in the nucleus accumbens (NAc) at 30 min with no change in protein expression. This effect was sensitive to mecamylamine and DHβE but not MLA, indicating that it is dependent on α4 subunit containing nicotinic receptors. Furthermore, TPM, but not nicotine, increased DAT function in the dorsal striatum at 1 h in a nicotinic receptor independent manner with no change in DAT protein expression. At 1 h DAT mRNA in the ventral tegmental area was decreased by both acute and chronic TPM treatments.

Standardizing Thin-Film Rotating Disk Electrode Measurements of the Oxygen Reduction Activity of Pt/C

Rotating disk electrode voltammetry has been touted as a simple means for benchmarking the oxygen reduction activity of platinum-based catalysts in proton exchange membrane fuel cells. The RDE methodology is still highly variable across laboratories, and due to differences in experimental conditions, up to 2.5x differences in mass activities are reported in recent literature from the same catalyst. We demonstrate an RDE protocol, and show that it can be replicated in two different laboratories. Uniform RDE methodology should be developed so that advanced catalysts can be compared between laboratories.

Proton–Electron Transport and Transfer in Electrocatalytic Films. Application to a Cobalt-Based O2-Evolution Catalyst

Solar-driven electrochemical transformations of small molecules, such as water splitting and CO2 reduction, pertinent to modern energy challenges, require the assistance of catalysts preferably deposited on conducting or semiconducting surfaces. Understanding mechanisms and identifying the factors that control the functioning of such systems are required for rational catalyst optimization and improved performance. A methodology is proposed, in the framework of rotating disk electrode voltammetry, to analyze the current responses expected in the case of a semigeneral reaction scheme involving a proton-coupled catalytic reaction associated with proton-coupled electron hopping through the film as rate controlling factors in the case where there is no limitation by substrate diffusion. The predictions concern the current density vs overpotential (Tafel) plots and their dependence on buffer concentration (including absence of buffer), film thickness and rotation rate. The Tafel plots may have a variety of slopes (e.g., F/RT ln 10, F/2RT ln 10, 0) that may even coexist within the overpotential range of a single plot. We show that an optimal film thickness exists beyond which the activity of the film plateaus. Application to water oxidation by films of a cobalt-based oxidic catalyst provides a successful test of the applicability of the proposed methodology, which also provides further insight into the mechanism by which these cobalt-based films catalyze the oxidation of water. The exact nature of the kinetic and thermodynamic characteristics that have been derived from the analysis is discussed as well as their use in catalyst benchmarking.

Impact of 1 mmol dm−3 concentrations of small molecules containing nitrogen-based cationic groups on the oxygen reduction reaction on polycrystalline platinum in aqueous KOH (1 mol dm−3)

Alkaline anion-exchange membranes (AAEMs) containing cationic head-groups (e.g. involving quaternary ammonium and imidazolium groups) are of interest with regard to application in alkaline polymer electrolyte fuel cells (APEFCs). This initial ex situ study evaluated the effect of 1 mmol dm(-3) concentrations of model molecules containing (AAEM-relevant) cationic groups on the oxygen reduction reaction on a polycrystalline platinum disk (Ptpc) electrode in aqueous KOH (1 mol dm(-3)). The cationic molecules studied were tetramethylammonium (TMA), benzyltrimethylammonium (BTMA), 1-benzyl-3-methylimidazolium (BMI), 1-benzyl-4-aza-1-azoniabicyclo[2.2.2]octane (BAABCO) and 6-(benzyloxy)-N,N,N-trimethylhexan-1-aminium (BOTMHA). Both cyclic and hydrodynamic linear sweep rotating disk electrode voltammetry techniques were used. The resulting voltammograms, derived estimates of apparent electrochemically active surface areas, Tafel slopes, apparent exchange-current densities and the number of electrons transferred (per O2 molecule) were compared. The results strongly suggest that 1 mmol dm(-3) concentrations of BTMA, BAABCO, and (especially) BMI seriously inhibit the catalytic activities of Ptpc in an aqueous KOH electrolyte at 25 °C. The negative influence of (benzene-ring-free) TMA and Cl(-) anions (KCl control experiment) appeared to be less severe. The separation of the trimethylammonium group from the benzene ring via a hexyloxy spacer chain (in BOTMHA) also produced a milder negative effect.

Photocatalytic generation of hydrogen from water using a cobalt pentapyridine complex in combination with molecular and semiconductor nanowire photosensitizers

Recently, a family of cobalt pentapyridine complexes of the type [(R-PY5Me2)Co(H2O)])(CF3SO3)2, (R = CF3, H, or NMe2; PY5Me2 = 2,6-bis(1,1-di(pyridin-2-yl)ethyl)pyridine) were shown to catalyze the electrochemical generation of hydrogen from neutral aqueous solutions using a mercury electrode. We now report that the CF3 derivative of this series, [(CF3PY5Me2)Co(H2O)](CF3SO3)2 (1), can also operate in neutral water as an electrocatalyst for hydrogen generation under soluble, diffusion-limited conditions on a glassy carbon electrode, as well as a photocatalyst for hydrogen production using either molecular or semiconductor nanowire photosensitizers. Owing to its relatively low overpotential compared to other members of the PY5 family, complex 1 exhibits multiple redox features on glassy carbon, including a one-proton, one-electron coupled oxidative wave. Further, rotating disk electrode voltammetry measurements reveal the efficacy of 1 as a competent hydrogen evolution catalyst under soluble, diffusion-limited conditions. In addition, we establish that 1 can also generate hydrogen from neutral water under photocatalytic conditions with visible light irradiation (λirr ≥ 455 nm), using [Ru(bpy)3]2+ as a molecular inorganic chromophore and ascorbic acid as a sacrificial donor. Dynamic light scattering measurements show no evidence for nanoparticle formation for the duration of the photolytic hydrogen evolution experiments. Finally, we demonstrate that 1 is also able to enhance the hydrogen photolysis yield of GaP nanowires in water, showing that this catalyst is compatible with solid-state photosensitizers. Taken together, these data establish that the well-defined cobalt pentapyridine complex [(CF3PY5Me2)Co(H2O)]2+ is a versatile catalyst for hydrogen production from pure aqueous solutions using either solar or electrical input, providing a starting point for integrating molecular systems into sustainable energy generation devices.

Oxidation-state dependent electrocatalytic activity of iridium nanoparticles supported on graphene nanosheets

Nanocomposites of iridium nanoparticles (Ir NPs), supported on graphene nanosheets, are synthesized and their electrocatalytic acitivities in the oxygen reduction reaction (ORR) are studied depending on their Ir oxidation state. Graphene functionalized with poly(vinyl pyrrolidone) (pRGO) is a suitable support for Ir NPs, producing well-monodispersed Ir NPs anchored strongly on the pRGO surface (Ir NP/pRGO) with a very high density. This was confirmed by scanning electron microscopy and transmission electron microscopy. The ORR activity of the Ir NP/pRGO nanocomposites in 0.5 M H2SO4 solution was observed to be dependent on the oxidation state of the immobilized Ir NPs. In fact, the nanocomposite composed of Ir(0) metal NPs, rather than Ir oxide (IrOx) NPs, exhibits higher ORR activity, such as more positive onset potential, higher and flatter limiting current density, a greater n value, and a sharper curve shape in the rotating disk electrode voltammetry experiments. Higher ORR activity of Ir is ascribed to the stronger adsorption of oxygen on the surface of Ir compared to IrOx. The practical stability of the Ir NP/pRGO composite was also confirmed under O2 saturated/acidic conditions.

Kinetics and mechanism of oxygen reduction in a protic ionic liquid

The oxygen reduction reaction (ORR) has been studied at Pt surfaces in the protic ionic liquid diethylmethylammonium trifluoromethanesulfonate. Water content measurements suggested that the ORR proceeded in the ionic liquid predominantly via a 4-electron reduction to water. A mechanistic analysis using rotating ring-disk electrode (RRDE) voltammetry confirmed that negligible amounts of hydrogen peroxide were formed during the ORR. A kinetic analysis of the ORR was performed using rotating disk electrode (RDE) voltammetry and the importance of correcting for ohmic (iR) drop prior to performing kinetic measurements in the ionic liquid is demonstrated. A Tafel analysis of the RDE voltammetry data revealed a change in the ORR Tafel slope from 70 mV per decade at low ORR overpotentials to 117 mV per decade at high overpotentials, and the reason for this change is discussed. The change in the Tafel slope for the ORR with increasing overpotential meant that the exchange current density for the ORR varied from 0.007 nA cm(-2) to 10 nA cm(-2), depending on the applied potential. Finally, the implications of these results for the development of protic ionic liquid fuel cells are discussed.

Importance of cholesterol in dopamine transporter function

The conformation and function of the dopamine transporter (DAT) can be affected by manipulating membrane cholesterol, yet there is no agreement as to the impact of cholesterol on the activity of lipid-raft localized DATs compared with non-raft DATs. Given the paucity of information regarding the impact of cholesterol on substrate efflux by the DAT, this study explores its influence on the kinetics of DAT-mediated DA efflux induced by dextroamphetamine, as measured by rotating disk electrode voltammetry (RDEV). Treatment with methyl-β-cyclodextrin (mβCD), which effectively depletes total membrane cholesterol--uniformly affecting cholesterol-DAT interactions in both raft and non-raft membrane domains--reduced both DA uptake and efflux rate. In contrast, disruption of raft-localized DAT by cholesterol chelation with nystatin had no effect, arguing against a vital role for raft-localized DAT in substrate uptake or efflux. Supranormal repletion of cholesterol-depleted cells with the analog desmosterol, a non-raft promoting sterol, was as effective as cholesterol itself in restoring transport rates. Further studies with Zn(2+) and the conformationally biased W84L DAT mutant supported the idea that cholesterol is important for maintaining the outward-facing DAT with normal rates of conformational interconversions. Collectively, these results point to a role for direct cholesterol-DAT interactions in regulating DAT function.

5‐HT1B autoreceptor regulation of serotonin transporter activity in synaptosomes

Serotonin-1B (5-HT(1B) ) autoreceptors are located in serotonin (5-HT) terminals, along with serotonin transporters (SERT), and play a critical role in autoregulation of serotonergic neurotransmission and are implicated in disorders of serotonergic function, particularly emotional regulation. SERT modulates serotonergic neurotransmission by high-affinity reuptake of 5-HT. Alterations in SERT activity are associated with increased risk for depression and anxiety. Several neurotransmitter receptors are known to regulate SERT K(m) and V(max) , and previous work suggests that 5-HT(1B) autoreceptors may regulate 5-HT reuptake, in addition to modulating 5-HT release and synthesis. We used rotating disk electrode voltammetry to investigate 5-HT(1B) autoreceptor regulation of SERT-mediated 5-HT uptake into synaptosomes. The selective 5-HT(1B) antagonist SB224289 decreased SERT activity in synaptosomes prepared from wild-type but not 5-HT(1B) knockout mice, whereas SERT uptake was enhanced after pretreatment with the selective 5-HT(1B) agonist CP94253. Furthermore, SERT activity varies as a function of 5-HT(1B) receptor expression-specifically, genetic deletion of 5-HT(1B) decreased SERT function, while viral-mediated overexpression of 5-HT(1B) autoreceptors in rat raphe neurons increased SERT activity in rat hippocampal synaptosomes. Considered collectively, these results provide evidence that 5-HT(1B) autoreceptors regulate SERT activity. Because SERT clearance rate varies as a function of 5-HT(1B) autoreceptor expression levels and is modulated by both activation and inhibition of 5-HT(1B) autoreceptors, this dynamic interaction may be an important mechanism of serotonin autoregulation with therapeutic implications.

Oxygen Reduction Reactions in Ionic Liquids and the Formulation of a General ORR Mechanism for Li–Air Batteries

Oxygen reduction and evolution reactions (ORRs and OERs) have been studied in ionic liquids containing singly charged cations having a range of ionic radii, or charge densities. Specifically, ORR and OER mechanisms were studied using cyclic and rotating disk electrode voltammetry in the neat ionic liquids (ILs), 1-ethyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide (EMITFSI) and 1-methyl-1-butyl-pyrrolidinium bis(triflouromethanesulfonyl)imide (PYR14TFSI), and in their solutions containing LiTFSI, NaPF6, KPF6, and tetrabutylammonium hexafluorophosphate (TBAPF6). A strong correlation was found between the ORR products and the ionic charge density, including those of the ionic liquids. The observed trend is explained in terms of the Lewis acidity of the cation present in the electrolyte using an acidity scale created from 13C NMR chemical shifts and spin–lattice relaxation (T1) times of 13C═O in solutions of these charged ions in propylene carbonate (PC). The ionic liquids lie in a continuum of a ca...

Electrocatalysis of oxygen reduction reaction on polyaniline-derived nitrogen-doped carbon nanoparticle surfaces in alkaline media

Nitrogen-doped carbon nanomaterials were synthesized by the carbonization of three different nanostructured polyaniline (PANI) salt precursors: PANI 3,5-dinitrosalicylate nanorods, PANI 5-sulfosalicylate nanorods/nanotubes, and PANI hydrogen sulfate nanorods/nanotubes/nanosheets. A comparative study of the electrocatalytic activity of these materials for oxygen reduction reaction (ORR) in alkaline solution was performed by using rotating disk electrode voltammetry. The electrochemical data were correlated to the structural and textural data obtained by Raman spectroscopy, X-ray diffractometry, X-ray photoelectron spectroscopy, elemental analysis and nitrogen sorption analysis. A fine interplay of textural characteristics, overall content of surface nitrogen and content of specific surface nitrogen functional groups were found to be responsible for a considerable variations in electrocatalytic properties toward ORR, involving variations in apparent number of electrons exchanged per O2 molecule (from 2 to nearly 4) and variations in onset potential. The catalyst loading was found to influence remarkably the ORR kinetics. The excellent electrocatalytic activity was found for carbonized PANI 5-sulfosalicylate. Namely, it exhibited the most positive onset potential amounting to −0.05 V vs. SCE at a catalyst loading of 500 μgcm−2. The interrelation between the electrocatalytic activity and the electrical double layer charging/discharging characteristics of the investigated N-doped nanocarbon materials was revealed.