Electrodeposited Cobalt Nanosheets on Smooth Silver as a Bifunctional Catalyst for OER and ORR: In Situ Structural and Catalytic Characterization

Developing earth-abundant, cost-effective, and active bifunctional electrocatalysts for oxygen reduction reaction (ORR) and oxygen evolution reaction (OER) is key to boosting sustainable energy systems such as electrolyzers and lithium-air batteries. However, the performance of promising cobalt-based materials is impaired by the external effects of binders and carbon additives as well as inhomogeneous electrode fabrication. In this work, binder- and carbon-free flower-like Co-decorated Ag catalytic nanosheets were in situ-synthesized via a simple electrodeposition approach. The morphology, composition, and structure of Co/Ag before and after OER were characterized using scanning electron microscopy (SEM), energy-dispersive X-ray (EDX), X-ray photoelectron spectroscopy (XPS), and X-ray diffraction (XRD). Co/Ag thin film electrodes with various Co contents exhibited a bifunctional activity toward ORR and OER due to a synergistic effect. XPS analysis suggested the formation of Co₃O₄ as the main active species for OER. In particular, Co (83%)/Ag surface revealed a 60 mV lower ORR overpotential than a pure Ag surface and even lower than drop-casted Co₃O₄ nanoparticles on Ag surface. Only 1.5% peroxide was generated, suggesting a four-electron transfer ORR. In addition, the OER onset potential on Co/Ag is 60 mV less than Co₃O₄. Tafel slopes of 71 and 75 mV dec^-1 were obtained for ORR and OER, respectively. Importantly, the three-dimensional (3D) growth mechanism of a cobalt layer (∼1 nm) on a well-defined atomic smooth Ag surface is unraveled by in situ electrochemical scanning tunneling microscopy (EC-STM). EC-STM suggests that Co prefers to nucleate at the step edges of Ag and grows in a 3D, forming nanoparticles, where the deposition/dissolution process of the Co adlayer on Ag is reversible. This investigation may provide insights into design strategies of efficient oxygen electrocatalysts.

Electrochemical Reduction of O2 in Ca2+ -Containing DMSO: Role of Roughness and Single Crystal Structure

In this study, the oxygen reduction reaction (ORR) in Ca2+ -containing dimethyl sulfoxide (DMSO) at well-ordered and rough electrode surfaces is compared by using cyclic voltammetry, differential electrochemical mass spectrometry, rotating ring disk electrode, and atomic force microscopy measurements. Slightly soluble CaO2 is the main product during early ORR on gold electrodes; after completion of a monolayer of CaO and/or CaO2 , which is formed in parallel and in competition to the peroxide, only superoxide is formed. When the monolayer is completely closed on smooth annealed Au, no further reduction occurs, whereas on rough Au a defect-rich layer allows for continuous formation of superoxide. CaO2 formed either via two subsequent 1 e - transfer steps or by disproportionation of superoxide may be deposited on top of the CaO/CaO2 adsorbate layer. The slow dissolution of the peroxide particles is demonstrated by AFM. Whereas a smooth CaO/CaO2 -covered electrode shows severe deactivation and a CaO/CaO2 -covered rough electrode allows for diffusion-limited superoxide formation, on single crystals peroxide formation is more pronounced. The reason is most likely the lack of nucleation sites for the blocking CaO/CaO2 layer. RRDE investigations showed sluggish reoxidation kinetics of the dissolved peroxide, which are most likely due to ion pairing with Ca2+ . The apparent transfer coefficient is estimated by using variation of the electrode roughness, confirming the result of the usual Tafel analysis and indicating an equilibrated first 1 e - transfer.

In situ friction study of Ag Underpotential deposition (UPD) on Au(111) in aqueous electrolyte

The electrodeposition of silver on Au(111) was investigated using lateral force microscopy (LFM) in Ag+ containing sulfuric acid. Friction force images show that adsorbed sulfate forms3 × 7 R 19 . 1 ∘ structure (θ s u l f a t e = 0 . 2 ) on Au(111) prior to Ag underpotential deposition (UPD) and ( 3 × 3 R 30 ∘ ) structure (θ s u l f a t e = 0 . 33 ) on a complete monolayer or bilayer of Ag. Variation of friction with normal load shows a non-monotonous dependence, which is caused by increasing penetration of the tip into the sulfate adlayer. In addition, the friction force is influenced by the varying coverage and mobility of Ag atoms on the surface. Before Ag coverage reaches the critical value, the deposited silver atoms may be mobile enough to be dragged by the movement of AFM tip. Possible penetration of the tip into the UPD layer at very high loads is discussed as a model for self-healing wear. However, when the coverage of Ag is close to 1, the deposited Ag atoms are tight enough to resist the influence of the AFM tip and the tip penetrates only into the sulfate adlayer.

Mixed Lithium and Sodium Ion Aprotic DMSO Electrolytes for Oxygen Reduction on Au and Pt Studied by DEMS and RRDE

In order to advance the development of metal-air batteries and solve possible problems, it is necessary to gain a fundamental understanding of the underlying reaction mechanisms. In this study we investigate the oxygen reduction reaction (ORR) and oxygen evolution reaction (OER, from species formed during ORR) in Na+ containing dimethyl sulfoxide (DMSO) on poly and single crystalline Pt and Au electrodes. Using a rotating ring disk electrode (RRDE) generator collector setup and additional differential electrochemical mass spectrometry (DEMS), we investigate the ORR mechanism and product distribution. We found that the formation of adsorbed Na2O2, which inhibits further oxygen reduction, is kinetically favored on Pt overadsorption on Au. Peroxide formation occurs to a smaller extent on the single crystal electrodes of Pt than on the polycrystalline surface. Utilizing two different approaches, we were able to calculate the heterogeneous rate constants of the O2/O2− redox couple on Pt and Au and found a higher rate for Pt electrodes compared to Au. We will show that on both electrodes the first electron transfer (formation of superoxide) is the rate-determining step in the reaction mechanism. Small amounts of added Li+ in the electrolyte reduce the reversibility of the O2/O2− redox couples due to faster and more efficient blocking of the electrode by peroxide. Another effect is the positive potential shift of the peroxide formation on both electrodes. The reaction rate of the peroxide formation on the Au electrode increases when increasing the Li+ content in the electrolyte, whereas it remains unaffected on the Pt electrode. However, we can show that the mixed electrolytes promote the activity of peroxide oxidation on the Pt electrode compared to a pure Li+ electrolyte. Overall, we found that the addition of Li+ leads to a Li+-dominated mechanism (ORR onset and product distribution) as soon as the Li+ concentration exceeds the oxygen concentration.

Graphical abstract

The Oxygen Reduction Reaction in Ca2+ -Containing DMSO: Reaction Mechanism, Electrode Surface Characterization, and Redox Mediation*

In this study the fundamental understanding of the underlying reactions of a possible Ca-O2 battery using a DMSO-based electrolyte was strengthened. Employing the rotating ring disc electrode, a transition from a mixed process of O2 - and O2 2- formation to an exclusive O2 - formation at gold electrodes is observed. It is shown that in this system Ca-superoxide and Ca-peroxide are formed as soluble species. However, there is a strongly adsorbed layer of products of the oxygen reduction reaction (ORR) s on the electrode surface, which is blocking the electrode. Surprisingly the blockade is only a partial blockade for the formation of peroxide while the formation of superoxide is maintained. During an anodic sweep, the ORR product layer is stripped from the electrode surface. With X-ray photoelectron spectroscopy (XPS) the deposited ORR products were shown to be Ca(O2 )2 , CaO2 , and CaO as well as side-reaction products such as CO3 2- and other oxygen-containing carbon species. It is shown that the strongly attached layer on the electrocatalyst, that was partially blocking the electrode, could be adsorbed CaO. The disproportionation reaction of O2 - in presence of Ca2+ was demonstrated via mass spectrometry. Finally, the ORR mediated by 2,5-di-tert-1,4-benzoquinone (DBBQ) was investigated by differential electrochemical mass spectrometry (DEMS) and XPS. Similar products as without DBBQ are deposited on the electrode surface. The analysis of the DEMS experiments shows that DBBQ- reduces O2 to O2 - and O2 2- , whereas in the presence of DBBQ2- O2 2- is formed. The mechanism of the ORR with and without DBBQ is discussed.

SLIM: A Short-Linked, Highly Redox-Stable Trityl Label for High-Sensitivity In-Cell EPR Distance Measurements

The understanding of biomolecular function is coupled to knowledge about the structure and dynamics of these biomolecules, preferably acquired under native conditions. In this regard, pulsed dipolar EPR spectroscopy (PDS) in conjunction with site-directed spin labeling (SDSL) is an important method in the toolbox of biophysical chemistry. However, the currently available spin labels have diverse deficiencies for in-cell applications, for example, low radical stability or long bioconjugation linkers. In this work, a synthesis strategy is introduced for the derivatization of trityl radicals with a maleimide-functionalized methylene group. The resulting trityl spin label, called SLIM, yields narrow distance distributions, enables highly sensitive distance measurements down to concentrations of 90 nm, and shows high stability against reduction. Using this label, the guanine-nucleotide dissociation inhibitor (GDI) domain of Yersinia outer protein O (YopO) is shown to change its conformation within eukaryotic cells.

Online Monitoring of Electrochemical Carbon Corrosion in Alkaline Electrolytes by Differential Electrochemical Mass Spectrometry

Carbon corrosion at high anodic potentials is a major source of instability, especially in acidic electrolytes and impairs the long-term functionality of electrodes. In-depth investigation of carbon corrosion in alkaline environment by means of differential electrochemical mass spectrometry (DEMS) is prevented by the conversion of CO2 into CO3 2- . We report the adaptation of a DEMS system for online CO2 detection as the product of carbon corrosion in alkaline electrolytes. A new cell design allows for in situ acidification of the electrolyte to release initially dissolved CO3 2- as CO2 in front of the DEMS membrane and its subsequent detection by mass spectrometry. DEMS studies of a carbon-supported nickel boride (Nix B/C) catalyst and Vulcan XC 72 at high anodic potentials suggest protection of carbon in the presence of highly active oxygen evolution electrocatalysts. Most importantly, carbon corrosion is decreased in alkaline solution.

Antimony deposition onto Au(111) and insertion of Mg

Magnesium-based secondary batteries have been regarded as a viable alternative to the immensely popular Li-ion systems owing to their high volumetric capacity. One of the largest challenges is the selection of Mg anode material since the insertion/extraction processes are kinetically slow because of the large ionic radius and high charge density of Mg²⁺ compared with Li⁺. In this work, we prepared very thin films of Sb by electrodeposition on a Au(111) substrate. Monolayer and multilayer deposition (up to 20 monolayers) were characterized by cyclic voltammetry (CV) and scanning tunneling microscopy (STM). Monolayer deposition results in a characteristic row structure; the monolayer is commensurate in one dimension, but not in the other. The row structure is to some extent maintained after deposition of further layers. After dissolution of the Sb multilayers the substrate is roughened on the atomic scale due to alloy formation, as demonstrated by CV and STM. Further multilayer deposition correspondingly leads to a rough deposit with protrusions of up to 3 nm. The cyclic voltammogram for Mg insertion/de-insertion from MgCl₂/AlCl₃/tetraglyme (MACC/TG) electrolyte into/from a Sb-modified electrode shows a positive shift (400 mV) of the onset potential of Mg deposition compared to that of a bare Au electrode. From the charge of the Mg deposition, we find that the ratio of Mg to Sb is 1:1, which is somewhat less than expected for the Mg₃Sb₂ alloy.

Antimony deposition onto Au (111) and insertion of Mg.. [DOI: 10.3762/bxiv.2019.113.v1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0]

Magnesium based secondary batteries have been regarded as a viable alternative compared to the immensely popular Li-ion systems owing to its high volumetric capacity. One of the largest challenges is the selection of Mg anode material since the insertion/extraction processes are kinetically slow because the large ionic radius and high charge density of Mg2+ compared with Li+.

We prepared very thin films of Sb by electrodeposition on an Au (111) substrate. Monolayer and multilayer deposition (up to 20 Monolayer) were characterized by cyclic voltammetry and STM (Scanning-Tunneling-Microscope). Monolayer deposition results in a characteristic row structure; the monolayer is commensurate in one dimension, but not in the other. The row structure is to some extent maintained after deposition of further layers. After dissolution of the multilayers of Sb the substrate is roughened on the atomic scale due to alloy formation, as demonstrated by CV and STM. Further multilayer deposition correspondingly leads to rough deposit with protrusion of up to 3 nm.

The cyclic voltammogram for Mg insertion/de-insertion from MgCl2/AlCl3/Tetraglyme (MACC/TG) electrolyte into/from Sb modified electrode shows a positive shift (400 mV) of the onset potential of Mg deposition compared to that at bare Au electrode. From the charge of Mg deposition, we find that the ratio of Mg to Sb is 1:1; and this somewhat less than expected for the Mg3Sb2 alloy.

Electrogeneration of inorganic chloramines on boron-doped diamond anodes during electrochemical oxidation of ammonium chloride, urea and synthetic urine matrix

Ubiquitous presence of chloride in water effluents may result in the unavoidable electrogeneration of active chlorine species when considering the application of electrochemical advanced oxidation processes as water treatment technologies. However, less attention has been drawn to the subsequent generation of other combined chlorine species such as chloramines. In this work, the electrogeneration of chloramines has been assessed in different water matrices containing NHCl₄, urea or synthetic urine. The yield of chloramines has been followed in-situ by differential electrochemistry mass spectroscopy (DEMS) during electrochemical advanced oxidation process with boron-doped diamond (BDD) anodes. Furthermore, the influence of several variables such as chloride concentration, pH or organics concentration on the different distribution of inorganic monochloramine, dichloramine and trichloramine released as products has been considered.

Polyphenols from Rheum Roots Inhibit Growth of Fungal and Oomycete Phytopathogens and Induce Plant Disease Resistance

A growing world population requires an increase in the quality and quantity of food production. However, field losses due to biotic stresses are currently estimated to be between 10 and 20% worldwide. The risk of resistance and strict pesticide legislation necessitate innovative agronomical practices to adequately protect crops in the future, such as the identification of new substances with novel modes of action. In the present study, liquid chromatography mass spectrometry was used to characterize Rheum rhabarbarum root extracts that were primarily composed of the stilbenes rhaponticin, desoxyrhaponticin, and resveratrol. Minor components were the flavonoids catechin, epicatechin gallate, and procyanidin B1. Specific polyphenolic mixtures inhibited mycelial growth of several phytopathogenic fungi and oomycetes. Foliar spray applications with fractions containing stilbenes and flavonoids inhibited spore germination of powdery mildew in Hordeum vulgare with indications of synergistic interactions. Formulated extracts led to a significant reduction in the incidence of brown rust in Triticum aestivum under field conditions. Arabidopsis thaliana mutant and quantitative reverse-transcription polymerase chain reaction studies suggested that the stilbenes induce salicylic acid-mediated resistance. Thus, the identified substances of Rheum roots represent an excellent source of antifungal agents that can be used in horticulture and agriculture.

Mono and dual hetero-structured M@poly-1,2 diaminoanthraquinone (M = Pt, Pd and Pt–Pd) catalysts for the electrooxidation of small organic fuels in alkaline medium

Oxidation of some small organic fuels such as methanol (MeOH), ethanol (EtOH) and ethylene glycol (EG) was carried out in an alkaline medium using palladium (Pd)–platinum (Pt) nanoparticles/poly1,2-diaminoanthraquinone/glassy carbon (p1,2-DAAQ/GC) catalyst electrodes. Pd and Pt were incorporated into the p1,2-DAAQ/GC electrode using the cyclic voltammetry (CV) technique. The obtained Pd/p1,2-DAAQ/GC, Pt/p1,2-DAAQ/GC, Pt/Pd/p1,2-DAAQ/GC and Pd/Pt/p1,2-DAAQ/GC nanocatalyst electrodes were characterized by scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDX) and CV methods. Real active surface area (A_real) achieved by carbon monoxide (CO) adsorption using differential electrochemical mass spectroscopy (DEMS) technique. The electrochemical activity was evaluated and normalized to A_real per metal loading mass. The electrocatalytic oxidation of the small organic fuels at the prepared nanocatalyst electrodes was studied in 1.0 M NaOH solutions by CV and chronoamperometric (CA) techniques. Pt/Pd/p1,2-DAAQ/GC nanocatalyst electrode exhibited enhanced catalytic activity, better durability and higher tolerance to carbon monoxide generated in the oxidation reaction when compared with the other three studied nanocatalysts. The present investigation suggests that the studied nanocatalysts can be successfully applied in direct oxidation of small organic fuels, especially MeOH.

Oxidation reaction of some small organic fuels such as methanol, ethanol and ethylene glycol was carried out in alkaline medium at palladium (Pd)–platinum (Pt) nanoparticles/poly1,2-diaminoanthraquinone/glassy carbon catalyst electrodes.

K–O2 electrochemistry: achieving highly reversible peroxide formation

Differential electrochemical mass spectrometry and classical electrochemical methods reveal that electrochemically produced K₂O₂ can be reversibly reoxidized to O₂.

Fast and Simultaneous Determination of Gas Diffusivities and Solubilities in Liquids Employing a Thin-Layer Cell Coupled to a Mass Spectrometer, Part I: Setup and Methodology

Transport properties and solubilities of volatile species in liquid solutions are of high interest in different chemical, biological, and physical systems. In this work, a new approach for determining the diffusivity and solubility of gases in liquids simultaneously is presented. The method presented relies on the diffusion of a volatile species through a thin, liquid layer and the subsequent detection of the species using a mass spectrometer. Evaluation of the time development of the resulting transient yields the diffusion coefficient, while the concentration of the species in the liquid layer can be calculated from the steady-state value of the flux into the mass spectrometer. Apart from the geometry of the thin layer and the calibration constant of the mass spectrometer no additional or external data are required. Experimental results of the temperature-dependent solubility and diffusivity of oxygen in dimethyl sulfoxide are presented in our companion paper Part II and serve as a proof of concept.

Fast and Simultaneous Determination of Gas Diffusivities and Solubilities in Liquids Employing a Thin-Layer Cell Coupled to a Mass Spectrometer, Part II: Proof of Concept and Experimental Results

A new method for simultaneously determining gas diffusivities and solubilities in liquids was presented and discussed in detail in Part I of this series. In this part of the series, the new measurement cell was employed to determine oxygen solubilities and diffusivities in 20 different dimethyl sulfoxide-based electrolytes. In addition, a comparison to values available in literature was made. From the temperature dependence of the diffusivity between 20 and 40 °C an activation barrier of 19 kJ mol^-1 for the diffusion of oxygen in pure dimethyl sulfoxide was found. Moreover, qualitative agreement between Jones-Dole viscosity coefficients and the dependence of the diffusivity on the electrolyte concentration was confirmed. The temperature-dependent solubility measurements revealed an unexpected increase of the oxygen solubility for temperatures above 30 °C. While the oxygen solubility in the case of the alkali-perchlorates decreases with increasing electrolyte concentration, a pronounced salting-in effect for lithium bis(trifluoromethane)sulfonimide was observed.

Surface morphology and adlayer structure of Se on Rh(111)

The deposition of Se from SeO₃^2- solutions was examined in the submonolayer regime by cyclic voltammetry, scanning tunneling microscopy and atomic force microscopy. Up to a coverage of ca. 0.5 (Se atoms to substrate atoms) a smooth adlayer is obtained with a 2 × √3 structure. When the coverage is increased, at around 0.55 V further deposition is paralleled by a roughening starting at the monoatomic steps. The adsorbed Se is stable in the SeO₃^2- free solution. For coverages below 0.25, separate domains for the Se covered regions and Se free regions were observed for potentials above 0.6 V. Since this is the potential of the spike corresponding to adsorption of OH at the clean Rh(111) surface in HClO₄, we have to assume that Se and OH adsorb in separate domains. At lower potentials, where OH is desorbed, Se spreads over the complete surface which then appears completely smooth in the STM images. When the coverage is about 0.25 or above, the roughening is also observed in SeO₃^2- free solution, demonstrating that the rough structures are not due to disordered deposition, but really due to a roughening by place exchange.

How many surface atoms in Co3O4 take part in oxygen evolution? Isotope labeling together with differential electrochemical mass spectrometry

Understanding the mechanism underlying the oxygen evolution reaction (OER) on oxides is crucial for the development of many energy storage systems. Here, the mechanism of OER on a Co₃O₄ spinel catalyst is investigated in alkaline media using ¹⁸O-labeling combined with differential electrochemical mass spectrometry (DEMS). This work unravels the role of surface oxygen of the oxide in the OER. It is shown that in H₂¹⁸O-containing electrolyte the amount of ¹⁸O¹⁶O evolved increases from cycle to cycle together with a concomitant decrease of the amount of ¹⁶O₂ with each cycle before reaching a steady-state value. ¹⁸O¹⁶O is also evolved from a H₂¹⁶O solution on a Co₃O₄ electrode pre-treated in H₂¹⁸O-containing solution, indicating the formation of the ¹⁸O-labeled oxide in the previous step. Therefore, the oxide layer takes part in OER via an oxygen exchange mechanism. The total number of oxygen atoms of the oxide participating in OER is 0.1 to 0.2% of the total oxide loading, corresponding to about 10-30% of the surface atoms; these represent the catalytically active sites. Moreover, the real surface area of the catalyst is estimated using different methods (namely the ball model, double layer capacitance method, redox peak method, isotope exchange), and compared to the BET data. The surface areas calculated from the BET data, ball model and redox peak method are similar for small particles, which indicates their smooth surface; however they are smaller than that estimated from double-layer capacitance. For larger particles, the much larger surface area estimated from the redox peak in comparison to that expected from the ball model seems to be due to their roughness. Thus, this work highlights the importance of probing the mechanism when investigating the OER activity of a catalyst.

A new thin layer cell for battery related DEMS-experiments: the activity of redox mediators in the Li–O2 cell

The activity of four different redox mediators was investigated with DEMS. The paper provides information about the underlying mechanism of Li₂O₂ oxidation by a redox mediator as well as about the stability of the redox mediator.

Correction: Oxygen reduction and oxygen evolution in DMSO based electrolytes: the role of the electrocatalyst

Correction for 'Oxygen reduction and oxygen evolution in DMSO based electrolytes: the role of the electrocatalyst' by C. J. Bondue et al., Phys. Chem. Chem. Phys., 2015, 17, 25593-25606.

Stick-slip behaviour on Au(111) with adsorption of copper and sulfate

Several transitions in the friction coefficient with increasing load are found on Au(111) in sulfuric acid electrolyte containing Cu ions when a monolayer (or submonolayer) of Cu is adsorbed. At the corresponding normal loads, a transition to double or multiple slips in stick-slip friction is observed. The stick length in this case corresponds to multiples of the lattice distance of the adsorbed sulfate, which is adsorbed in a √3 × √7 superstructure on the copper monolayer. Stick-slip behaviour for the copper monolayer as well as for 2/3 coverage can be observed at F N ≥ 15 nN. At this normal load, a change from a small to a large friction coefficient occurs. This leads to the interpretation that the tip penetrates the electrochemical double layer at this point. At the potential (or point) of zero charge (pzc), stick-slip resolution persists at all normal forces investigated.

Oxygen reduction and oxygen evolution in DMSO based electrolytes: the role of the electrocatalyst

Electrochemical oxygen reduction to both peroxide and superoxide is an inner sphere reaction in DMSO.

Oxygen Reduction and Oxygen Evolution Reactions in Non-Aqueous Electrolyte As Studies By Dems

Secondary lithium-air batteries are promising candidates for a future energy storage system as they provide in theory high capacity; however, in practice they show bad cyclebility. The key step in discharging these batteries is the reduction of oxygen present in air. So far the oxygen reduction reaction (ORR) has been investigated thoroughly in aqueous media, but little research has been done in non-aqueous solvents.

Organic carbonates are unsuitable for the use in lithium-air batteries because they decompose upon charging [1]. Recently Scrosati [2] showed by XRD that tetraethylene glycol dimethyl ether (tetraglyme) is an appropriate electrolyte for Li-air battery whereas Bruce [3] using XRD and FTIR techniques demonstrated that, tetraglyme is not the best electrolyte because it decomposes in the first few cycles. On the other hand, Li2O2 has been reported as the major discharge product using dimethyl sulfoxide (DMSO) as an electrolyte [4].

Since spectroscopic techniques are superior to diffraction methods in detecting charge/discharge products, mass spectrometry in combination with electrochemistry (DEMS) has been used in this study to determine the electrolyte stability, water content, the amount of O2 reduced and evolved in a variety of aprotic electrolytes such as ethers (tetraglyme) and sulfoxide (DMSO). O2 solubility in aqueous and different non-aqueous electrolyte and its dependence on the flow rate of the electrolyte has been studied.

Crucial is a knowledge of the O2 solubility in these electrolytes. We will present a new method for its determination using differential electrochemical mass spectrometry (DEMS) based on the convection and diffusion behaviour characteristices of the dual thin layer cell used for DEMS. [5]

References:

[1] F. Mizuno, et al., Electrochemitry, 2010, 78, 403. [2] H Jung et al., Nat. Chem., 2012, 4, 579. [3] S. Freunberger, et al., Angew. Chem. Int. Ed., 2011, 50, 8609. [4] Z. Peng, et al., Science, 2012, 337, 563. [5] Fuhrmann, J.; Linke, A.; Langmach, H.; Baltruschat, H., Numerical calculation of the limiting current for a cylindrical thin layer flow cell Electrochimica Acta 2009, 55, 430-438.