Presented here is an electrochemical three-electrode Gas Diffusion Electrode (GDE) cell tailored for operandoand in situ investigations of electrocatalytic processes, with a particular focus on X-ray scattering studies. The optimized cell is engineered to accommodate the minimal sample-detector distances requisite for comprehensive X-ray total scattering investigations. An in-depth understanding of catalytic processes requires their study under 'working' conditions.
View Article and Find Full Text PDFHerein, we report a straightforward approach for the preparation of Pt-Au alloy nanoparticles from Pt + Au/C nanocomposites using monometallic colloidal nanoparticles as starting blocks. Four different compositions with fixed Pt content and varying Pt to Au mass ratios from 1:1 up to 1:7 were prepared as formic acid oxidation reaction (FAOR) catalysts. The study was carried out in a gas diffusion electrode (GDE) setup.
View Article and Find Full Text PDFHydrogen production from renewable resources and its reconversion into electricity are two important pillars toward a more sustainable energy use. The efficiency and viability of these technologies heavily rely on active and stable electrocatalysts. Basic research to develop superior electrocatalysts is commonly performed in conventional electrochemical setups such as a rotating disk electrode (RDE) configuration or H-type electrochemical cells.
View Article and Find Full Text PDFIn this work, we discuss the application of a gas diffusion electrode (GDE) setup for benchmarking electrocatalysts for the reductive conversion of CO₂ (CO₂ RR: CO₂ reduction reaction). Applying a silver nanowire (Ag-NW) based catalyst, it is demonstrated that in the GDE setup conditions can be reached, which are relevant for the industrial conversion of CO₂ to CO. This reaction is part of the so-called 'Rheticus' process that uses the CO for the subsequent production of butanol and hexanol based on a fermentation approach.
View Article and Find Full Text PDFIn the present work we investigate the structure sensitivity of the oxygen evolution reaction (OER) combining electrochemistry, in situ spectroscopy and density functional theory calculations. The intrinsic difficulty of such studies is the fact that at electrode potentials where the OER is observed, the electrode material is highly oxidized. As a consequence, the surface structure during the reaction is in general ill-defined and only scarce knowledge exists concerning the structure-activity relationship of this important reaction.
View Article and Find Full Text PDFACS Appl Mater Interfaces
November 2017
The oxygen reduction reaction (ORR) is one of the key processes in electrocatalysis. In this communication, the ORR is studied using a rotating disk electrode (RDE). In conventional work, this method limits the potential region where kinetic (mass transport free) reaction rates can be determined to a narrow range.
View Article and Find Full Text PDFGraphene is a promising candidate for an ideal membrane material. Its ultralow (one-atomic) thickness potentially provides high permeation and at the same time high selectivity. Here, it is shown that these properties can be used to create a confined, two-dimensional electrochemical environment between a graphene layer and a single-crystal Pt(111) surface.
View Article and Find Full Text PDFWe describe the development and test of an elevated pressure and temperature rotating disk electrode (RDE) system that allows measurements under well-defined mass transport conditions. As demonstrated for the oxygen reduction reaction on polycrystalline platinum (Pt) in 0.5M H2SO4, the setup can easily be operated in a pressure range of 1-101 bar oxygen, and temperature of 140 °C.
View Article and Find Full Text PDFWe present a detailed description of the construction and testing of an electrochemical cell setup allowing the investigation of a gas diffusion electrode containing carbon supported high surface area catalysts. The setup is designed for measurements in concentrated phosphoric acid at elevated temperature, i.e.
View Article and Find Full Text PDFWe present a detailed description of the construction and testing of an electrochemical cell allowing measurements at elevated temperature and pressure. The cell consists of a stainless steel pressure vessel containing the electrochemical glass cell exhibiting a three electrode configuration. The design of the working electrode is inspired by conventional rotating disk electrode setups.
View Article and Find Full Text PDFWe present a detailed description of the construction of an in situ electrochemical ATR-FTIR setup combined with a wall-jet electrode to investigate the electrocatalytic properties of nanoparticulate catalysts in situ under controlled mass transport conditions. The presented setup allows the electrochemical interface to be probed in combination with the simultaneous determination of reaction rates. At the same time, the high level of automation allows it to be used as a standard tool in electrocatalysis research.
View Article and Find Full Text PDFThe diminished surface-area-normalized catalytic activity of highly dispersed Pt nanoparticles compared with bulk Pt is particularly intricate, and not yet understood. Here we report on the oxygen reduction reaction (ORR) activity of well-defined, size-selected Pt nanoclusters; a unique approach that allows precise control of both the cluster size and coverage, independently. Our investigations reveal that size-selected Pt nanoclusters can reach extraordinarily high ORR activities, especially in terms of mass-normalized activity, if deposited at high coverage on a glassy carbon substrate.
View Article and Find Full Text PDFActa Orthop Scand
June 1988
At birth a girl sustained a displaced femoral fracture that healed with considerable shortening and angulation. The correction by growth of the deformity was followed radiographically during the entire 16-year growth period.
View Article and Find Full Text PDFActa Orthop Scand
December 1979
Sydsven Medicinhist Sallsk Arsskr
April 1980
Arch Orthop Trauma Surg (1978)
August 1978
Through 17 years ten patients were treated for psychologically unacceptable tallness by bilateral femoral shortening. All were young adults between 17 and 28 years; one was acromegalic, one had Marfans syndrome and the other were tall for unknown reasons. The amount of shortening obtained was between 6 and 16 cm.
View Article and Find Full Text PDFThe modern consumer is exposed to a wide variety of plastic and rubber products in his day to day life: at home, work, school, shopping, recreation and play, and transport. A large variety of toxic sequellae have resulted from untoward exposures by many different routes: oral, dermal, inhalation, and parenteral. Toxic change may result from the plastic itself, migration of unbound components and additives, chemical decomposition or toxic pyrolysis products.
View Article and Find Full Text PDFMeasurement of blood fluorocarbon levels was carried out in subjects exposed to a number of household aerosol products containing fluorocarbon gases as propellants. All aerosols were used according to manufacturers' recommendations. The general purpose of the study was to determine whether with normal routine exposure to a wide variety of household aerosol products fluorocarbon could be found in the blood and if so, to check the potential toxicity of the levels reached.
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