Nanoimpacts at Active and Partially Active Electrodes: Insights and Limitations

Roehrich, Brian; Sepunaru, Lior

doi:10.1002/ange.202007148

Cited by 4 publications

(3 citation statements)

References 62 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The observation of these stochastic events can provide information on various single nanoparticles contrary to ensemble (bulk) measurements [12–15] . The main advantage of studying collisions of single entities is the low limit of detection (in principle, one single species) inherent to this electroanalytical method and the ability to study single entities (cells, viruses, nanoparticles, etc.…) in real time (dynamic measurement) [16–27] …”

Section: Figurementioning

confidence: 99%

Detection of Bacterial Rhamnolipid Toxin by Redox Liposome Single Impact Electrochemistry

et al. 2021

View full text Add to dashboard Cite

The detection of Rhamnolipid virulence factor produced by Pseudomonas aeruginosa involved in nosocomial infections is reported by using the redox liposome single impact electrochemistry. Redox liposomes based on 1,2dimyristoyl-sn-glycero-3-phosphocholine as a pure phospholipid and potassium ferrocyanide as an encapsulated redox content are designed for using the interaction of the target toxin with the lipid membrane as a sensing strategy. The electrochemical sensing principle is based on the weakening of the liposomes lipid membrane upon interaction with Rhamnolipid toxin which leads upon impact at an ultramicroelectrode to the breakdown of the liposomes and the release/electrolysis of its encapsulated redox probe. We present as a proof of concept the sensitive and fast sensing of a submicromolar concentration of Rhamnolipid which is detected after less than 30 minutes of incubation with the liposomes, by the appearing of current spikes in the chronoamperometry measurement.

show abstract

Section: Figurementioning

confidence: 99%

Detection of Bacterial Rhamnolipid Toxin by Redox Liposome Single Impact Electrochemistry

et al. 2021

View full text Add to dashboard Cite

show abstract

“…Co-located Raman microscopy and field emission-scanning electron microscopy allow unambiguous characterization of the sites of the electrochemical measurements in a correlative multi-microscopy approach, 47,55 while the copper substrate surface crystallography upon which the graphene sits, can also be mapped with electron backscatter diffraction (EBSD) to determine any influence on the electrochemical response. [56][57][58][59][60][61] We focus on the ET kinetics of [Ru(NH3)6] 3+/2+ , a classic example of OS-ET, [62][63][64][65][66] which has been used for studies of outer sphere electrochemistry at graphene, 38,67 and does not adsorb on graphene at a detectable level. 68 We establish that the ET rate is in the order monolayer > bilayer > multilayer graphene on copper.…”

Section: Introductionmentioning

confidence: 99%

Adiabatic versus Non-Adiabatic Electron Transfer at 2D Electrode Materials

Liu¹,

Kang²,

Perry³

et al. 2021

Preprint

View full text Add to dashboard Cite

<div><div><div><p>Outer-sphere electron transfer (OS-ET) is a cornerstone elementary electrochemical reaction, yet microscopic understanding is largely based on idealized theories, developed in isolation from experiments that themselves are often close to the kinetic (diffusion) limit. Focusing on graphene as-grown on a copper substrate as a model 2D material/metal-supported electrode system, this study resolves the key electronic interactions in OS-ET, and identifies the role of graphene in modulating the electronic properties of the electrode/electrolyte interface. An integrated experimental-theoretical approach combining co-located multi-microscopy, centered on scanning electrochemical cell microscopy (SECCM), with Raman microscopy and field emission-scanning electron microscopy, together with rate theory and density functional theory calculations is used to address OS-ET kinetics of hexaamineruthenium (III/II) chloride, [Ru(NH3)6]3+/2+. The experimental methodology allows spatially-resolved electrochemical measurements to be targeted at distinct regions of monolayer, bilayer and multilayer graphene on copper, with high diffusion rates, to reveal ET kinetics in the order: monolayer > bilayer > multilayer. Theoretical and computational methods combining the Schmickler-Newns-Anderson model, transition state theory, and constant potential DFT reveal that the difference in kinetics at monolayer and bilayer graphene can be rationalized in the context of a dominantly adiabatic mechanism, where the addition of subsequent graphene layers increases the contact potential, producing an increase in the effective barrier to electron transfer. This study provides a roadmap for the integration of experiments and theory in order to understand the nature of heterogeneous electron transfer at complex nanostructured electrode materials.</p></div></div></div>

show abstract

“…Co-located Raman microscopy and field emission-scanning electron microscopy allow unambiguous characterization of the sites of the electrochemical measurements in a correlative multi-microscopy approach, 49,57 while the copper substrate surface crystallography upon which the graphene sits, can also be mapped with electron backscatter diffraction (EBSD) to determine any influence on the electrochemical response. [58][59][60][61][62][63] We focus on the ET kinetics of [Ru(NH3)6] 3+/2+ , a classic example of OS-ET, [64][65][66][67][68] which has been used for studies of outer sphere electrochemistry at graphene, 40,69 and does not adsorb on graphene at a detectable level. 70 We establish that the ET rate is in the order monolayer > bilayer > multilayer graphene on copper.…”

Section: Introductionmentioning

confidence: 99%

Adiabatic versus Non-Adiabatic Electron Transfer at 2D Electrode Materials

Liu¹,

Kang²,

Perry³

et al. 2021

Preprint

View full text Add to dashboard Cite

<div><div><div><p>Outer-sphere electron transfer (OS-ET) is a cornerstone elementary electrochemical reaction, yet microscopic understanding is largely based on idealized theories, developed in isolation from experiments that themselves are often close to the kinetic (diffusion) limit. Focusing on graphene as-grown on a copper substrate as a model 2D material/metal-supported electrode system, this study resolves the key electronic interactions in OS-ET, and identifies the role of graphene in modulating the electronic properties of the electrode/electrolyte interface. An integrated experimental-theoretical approach combining co-located multi-microscopy, centered on scanning electrochemical cell microscopy (SECCM), with Raman microscopy and field emission-scanning electron microscopy, together with rate theory and density functional theory (DFT) calculations is used to address OS-ET kinetics of hexaamineruthenium (III/II) chloride, [Ru(NH3)6]3+/2+. The experimental methodology allows spatially-resolved electrochemical measurements to be targeted at distinct regions of monolayer, bilayer and multilayer graphene on copper, with high diffusion rates, to reveal ET kinetics in the order: monolayer > bilayer > multilayer. To rationalize these findings we extended the Schmickler-Newns-Anderson model Hamiltonian for electron transfer and parametrized it using constant potential DFT. Combining this model with rate theory reveals that the difference in kinetics at monolayer and bilayer graphene can be rationalized in the context of a dominantly adiabatic mechanism, where the addition of subsequent graphene layers increases the contact potential, producing an increase in the effective barrier to electron transfer. This study provides a roadmap for the integration of experiments, theory, and simulations in order to understand the nature of heterogeneous electron transfer at complex nanostructured electrode materials.</p></div></div></div>

show abstract

Nanoimpacts at Active and Partially Active Electrodes: Insights and Limitations

Cited by 4 publications

References 62 publications

Detection of Bacterial Rhamnolipid Toxin by Redox Liposome Single Impact Electrochemistry

Detection of Bacterial Rhamnolipid Toxin by Redox Liposome Single Impact Electrochemistry

Adiabatic versus Non-Adiabatic Electron Transfer at 2D Electrode Materials

Adiabatic versus Non-Adiabatic Electron Transfer at 2D Electrode Materials

Contact Info

Product

Resources

About