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

Jürmann, Gea; Tammeveski, Kaido

doi:10.1016/j.jelechem.2006.09.002

Cited by 101 publications

(62 citation statements)

References 47 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Thus, the increase in the percentage of inactivation from CNT to O-CNT (44% to 61%) is due to the introduction of functional surface defects, e.g., surface oxy-groups, such as carboxylates or quinones, on the walls and tips of the tubes and, in turn, an increase in reactivity (24). Annealing can either remove the functional groups to reveal undecorated defects and sharper tips (42) or alter the speciation of the functional surface groups, resulting in higher or lower reactivity (57). Since the OA-CNT used here contain only COO type functional groups according to XPS characterization, which are usually assigned to alcohols or ethers that have not been reported to be highly reactive (39), it is likely that the former reason is responsible for the observed increase in the percentage of inactivation on OA-CNT (67%).…”

Section: Discussionmentioning

confidence: 99%

Semiquantitative Performance and Mechanism Evaluation of Carbon Nanomaterials as Cathode Coatings for Microbial Fouling Reduction

Zhang

Nghiem

Silverberg

et al. 2015

Appl Environ Microbiol

View full text Add to dashboard Cite

In this study, we examine bacterial attachment and survival on a titanium (Ti) cathode coated with various carbon nanomaterials (CNM): pristine carbon nanotubes (CNT), oxidized carbon nanotubes (O-CNT), oxidized-annealed carbon nanotubes (OA-CNT), carbon black (CB), and reduced graphene oxide (rGO). The carbon nanomaterials were dispersed in an isopropyl alcoholNafion solution and were then used to dip-coat a Ti substrate. Pseudomonas fluorescens was selected as the representative bacterium for environmental biofouling. Experiments in the absence of an electric potential indicate that increased nanoscale surface roughness and decreased hydrophobicity of the CNM coating decreased bacterial adhesion. The loss of bacterial viability on the noncharged CNM coatings ranged from 22% for CB to 67% for OA-CNT and was dependent on the CNM dimensions and surface chemistry. For electrochemical experiments, the total density and percentage of inactivation of the adherent bacteria were analyzed semiquantitatively as functions of electrode potential, current density, and hydrogen peroxide generation. Electrode potential and hydrogen peroxide generation were the dominant factors with regard to short-term (3-h) bacterial attachment and inactivation, respectively. Extended-time electrochemical experiments (12 h) indicated that in all cases, the density of total deposited bacteria increased almost linearly with time and that the rate of bacterial adhesion was decreased 8-to 10-fold when an electric potential was applied. In summary, this study provides a fundamental rationale for the selection of CNM as cathode coatings and electric potential to reduce microbial fouling. Biofilm formation is ubiquitous in aquatic environments and is undesirable for industrial systems, such as heat exchangers and ship hulls (1), as well as for engineered environmental systems, such as membrane filters (2) and water distribution pipelines. A critical initial stage of biofouling involves microorganism adhesion and formation of the primary slime layer that allows for continued biofilm development (3, 4). Thus, if initial microorganism adhesion is reduced, continued biofilm development may be slowed as well.Continuous research efforts have been devoted to microbial fouling control, from the development of antimicrobial surfaces (5) to the disturbance of bacterial biofilm ecology by quorum sensing (6, 7). With regard to antimicrobial surfaces, the interfacial energy between a surface and water has been identified as a key factor in microbial adhesion, and hydrophilic surfaces generally hinder protein adsorption and, in turn, reduce biofouling (8). A highly charged cationic surface has also been demonstrated to kill bacteria and reduce fouling (9). However, since microbes have a complex and species-dependent surface chemistry, a permanently modified surface will not reduce biofouling for all microbes, and decreased antifouling performance is often observed in complex environments. One solution may be active biofouling reduction that can be tuned in situ ...

show abstract

Section: Discussionmentioning

confidence: 99%

Semiquantitative Performance and Mechanism Evaluation of Carbon Nanomaterials as Cathode Coatings for Microbial Fouling Reduction

Zhang

Nghiem

Silverberg

et al. 2015

Appl Environ Microbiol

View full text Add to dashboard Cite

show abstract

“…The anodic pre-treatment of GC increases the rate of O 2 reduction by creating a higher number of active carbon-oxygen functionalities on the surface [18,38]. Recently, the involvement of surface quinone groups has been proposed for electrocatalysis of oxygen reduction on multi-walled carbon nanotubes modified electrodes in alkaline solution [39].…”

Section: Introductionmentioning

confidence: 99%

The pH-dependence of oxygen reduction on quinone-modified glassy carbon electrodes

Jürmann

Schiffrin

Tammeveski

2007

Electrochimica Acta

Self Cite

118

View full text Add to dashboard Cite

“…Yang et al [37] showed that Pd/C catalysts in alkaline had high activity for ORR, and that the carbon support itself is active for the two-electron reduction of O 2 to peroxide (which can then migrate to the Pd particles for subsequent twoelectron reduction to water). It is shown that all carbon materials have some ORR activity in alkaline solution (but none in acid), normally for the twoelectron reduction to peroxide, although some oxidized carbon surfaces can complete the serial reduction to water at higher overpotentials [24,[38][39][40].…”

Section: The Orr Mechanismmentioning

confidence: 99%

Alkaline Anion Exchange Membrane Fuel Cells

Jervis¹,

Brett²

2014

Materials for Low‐Temperature Fuel Cells

View full text Add to dashboard Cite

Fuel cells represent a potentially integral technology in a greener electricitybased energy economy. Converting chemical energy directly into electricity with no moving parts and no particulate or greenhouse gas emissions at point of operation, they can offer higher efficiencies than combustion and greater energy storage and reduced "charge" times compared with batteries. While they retain few of the disadvantages of existing electricity generation technologies, a major barrier to commercialization and widespread use at present is cost. The key working part of a fuel cell, the membrane electrode assembly (MEA), comprises a catalyst, usually containing platinum, and an ionic polymer membrane, both of which contribute significantly to the overall cost of a fuel cell. This chapter will concentrate on the potential for alkaline anion exchange membrane (AAEM) fuel cells to provide a route to reduced costs and help realize commercial ubiquity of fuel cells in various energy sectors. We will first discuss the basic principles of the more common acidic PEM fuel cells and the thermodynamics and kinetics of the electrochemical reactions governing their operation, before explaining the key differences in AAEM fuel cells and how they might provide an advantage over the more established technology.This basic idea of the fuel cell goes back to as far as 1839 when Swanseaborn physicist Sir William Gove realized that reverse electrolysis of water was possible. However, development from this concept was slow and it was not until the 1960s and the Apollo Space Programme that fuel cells became practicable, in the form of aqueous alkaline electrolyte fuel cells. Aqueous electrolyte-based fuel cells have many disadvantages for portability causing recent focus to shift toward solid electrolytes, in particular toward polymer electrolyte membrane (PEM) fuel cells. These employ an ionomer, which is a polymer containing an ionic functional group in the monomer, as the electrolyte in order to allow hydrogen ion transport through a nonaqueous medium. Recent improvements in membrane technology, and in particular the performance of the industry standard Nafion membranes, have made PEM fuel cells a major focus of research. The alkaline 3 Materials for Low-Temperature Fuel Cells, First Edition. Edited

show abstract

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

Cited by 101 publications

References 47 publications

Semiquantitative Performance and Mechanism Evaluation of Carbon Nanomaterials as Cathode Coatings for Microbial Fouling Reduction

Semiquantitative Performance and Mechanism Evaluation of Carbon Nanomaterials as Cathode Coatings for Microbial Fouling Reduction

The pH-dependence of oxygen reduction on quinone-modified glassy carbon electrodes

Alkaline Anion Exchange Membrane Fuel Cells

Contact Info

Product

Resources

About