Ni-Fe oxyhydroxides are the most active known electrocatalysts for oxygen evolution reaction (OER) in alkaline electrolytes and therefore of great scientific technological importance context electrochemical energy conversion. Here we uncover, investigate, discuss previously unaddressed effects conductive supports electrolyte pH on Ni-Fe(OOH) catalyst redox behavior catalytic OER activity, combining situ UV-vis spectro-electrochemistry, operando mass spectrometry (DEMS), cryo X-ray absorption...

Go with the flow: A novel spectroelectrochemical flow cell well-defined mass transport allows time-resolved electrochemical and in situ FTIR spectroscopy measurements under continuous electrolyte (e.g. during exchange). Its potential for mechanistic kinetic studies was demonstrated on electrooxidation of formic acid. Supporting information this article is available WWW http://www.wiley-vch.de/contents/jc_2002/2006/z502172_s.pdf or from author. Please note: The publisher not responsible...

The ethanol oxidation reaction (EOR) on a carbon-supported Pt nanoparticle catalyst was studied by cyclic voltammetry and potential-step measurements as function of concentration temperature (23−60 °C), combining on-line mass spectrometric analysis the products electrochemical current measurements. effect loading/electrode roughness elucidated comparison with polycrystalline electrode. Individual, absolute rates for CO2 acetaldehyde formation were determined via doubly ionized carbon dioxide...

We present and discuss the results of an in situ IR study on mechanism kinetics formic acid oxidation a Pt film/Si electrode, performed attenuated total reflection (ATR) flow cell configuration under controlled mass transport conditions, which specifically aimed at elucidating role adsorbed bridge-bonded formates this reaction. Potentiodynamic measurements show complex interplay between formation desorption/oxidation COad formate species Faradaic current. The notably faster increase current...

The combination of differential electrochemical mass spectrometry (DEMS) and quartz crystal microbalance (EQCM) is possible by means a new dual thin layer cell. Thus, simultaneous real‐time measurements volatile products deposited (or dissolved) species can be performed, which demonstrated for CO‐adsorption desorption processes on Pt Pt‐Ru alloy in sulfuric acid. In particular, it shown that alloy, electrode anions are adsorbed even at 0 mV vs. reversible hydrogen electrode. © 1999...

Methanol oxidation on a supported Pt fuel cell catalyst was investigated by on-line differential electrochemical mass spectrometry (DEMS) at continuous electrolyte flow and defined utilization, employing thin-film electrode setup thin-layer flow-through cell. The active surface of the Pt/Vulcan (E-TEK) high area characterized quantitatively Hupd preadsorbed CO monolayer stripping. stripping DEMS experiments, oxidizing adsorbed dehydrogenation products formed upon methanol adsorption...

The interaction of colloid-based, carbon supported Pt/C (40 wt%), PtRu/C (45 wt%) and Pt3Sn/C (24 catalysts with ethanol their performance for electrooxidation were investigated in model studies by electrochemical, situ infrared spectroscopy on-line differential electrochemical mass spectrometry measurements. combined application spectroscopic techniques on realistic under reaction (DEMS, IR) transport conditions (DEMS) yields new insight mechanistic details the these above conditions. Based...

The interaction of ethanol and its oxidative C2 derivatives acetaldehyde acetic acid with a Pt thin film electrode in 0.5 M H2SO4 solution was investigated by situ Fourier transform infrared spectroscopy an attenuated total reflection configuration (ATR-FTIRS). Time-resolved spectro-electrochemical measurements were carried out under well-defined mass transport to/from the thin-layer flow cell setup, allowing to monitor electrode∣electrolyte interface formation/removal adsorbed species both...

The role of transport and re-adsorption processes on the oxygen reduction reaction (ORR), in particular its selectivity was studied using nanostructured model electrodes consisting arrays Pt nanostructures well-defined size separation a planar glassy carbon (GC) substrate. electrochemical measurements were performed under controlled conditions double-disk electrode thin-layer flow-cell configuration; fabricated by colloidal lithography techniques, yielding well defined density (diameter: 140...

In this study, we investigated the influence of thermal treatment, soaking in H2SO4 and electrochemical ageing on commercially available carbon felt materials from SGL carbon. We compared both pre-treatment (carbonization or graphitization) precursor (Rayon PAN). By thermogravimetric analysis coupled with mass spectrometry (TGA-MS) showed, that after stability was lower for carbonized felts to graphitized Rayon based were more stable than PAN ones. Soaking had a stronger impact felts,...

We have investigated the influence of catalyst loading (7−35 μgPt·cm-2) on methanol oxidation product yields over Vulcan XC72 supported Pt by differential electrochemical mass spectrometry (DEMS), both under potentiodynamic and potentiostatic (0.6 VRHE) conditions. Experiments were performed at room temperature continuous flow conditions (0.1 M CH3OH in 0.5 H2SO4 solution). Absolute calibration DEMS signal allowed determination current efficiencies for final reaction CO2 intermediates formic...

The potential of in-situ Fourier transform infrared (FTIR) spectroscopy measurements in an attenuated total reflection configuration (ATR-FTIRS) for the evaluation reaction pathways, elementary steps, and their kinetics is demonstrated formic acid electrooxidation on a Pt film electrode. Quantitative kinetic information two dehydration CO(ad) oxidation, contributions related pathways dual path mechanism are derived from IR spectroscopic signals simultaneous electrochemical ATR-FTIRS over...

The role of mesoscopic mass transport and re-adsorption effects in electrocatalytic reactions was investigated using the oxygen reduction reaction (ORR) as an example. electrochemical measurements were performed on structurally well-defined nanostructured model electrodes under controlled conditions a thin-layer flow cell. consist arrays Pt ultra-microelectrodes (nanodisks) defined size (diameter approximately 100 nm) separated planar glassy carbon (GC) substrate, which fabricated employing...

The determination of kinetic isotope effects (KIEs) for different reaction pathways and steps in a complex network, where KIEs may affect the overall various ways including dominant minority or buildup reaction-inhibiting adlayer, is demonstrated formic acid electrooxidation on Pt film electrode by quantitative electrochemical situ IR spectroscopic measurements under controlled mass-transport conditions. ability to separate resulting from contributions--which not possible using purely...

Photoelectrochemical water oxidation and photocatalytic H2 evolution on planar nanocrystalline Au/TiO2 catalyst film electrodes were studied by combined electrochemistry online mass spectrometry, allowing for the detection quantification of volatile reaction products O2 H2, thus, comparison with photocurrent, to determine selectivities map out contributions from side reactions. The catalysts prepared a photodeposition method deposited conductive glass substrates, measurements performed under...

Abstract Aqueous zinc–air batteries (ZABs) are a low‐cost, safe, and sustainable technology for stationary energy storage. ZABs with pH‐buffered near‐neutral electrolytes have the potential longer lifetime compared to traditional alkaline due slower absorption of carbonates at nonalkaline pH values. However, existing often contain halide salts, which corrosive threaten precipitation ZnO as dominant discharge product. This paper presents method designing halide‐free aqueous ZAB using...