74 research outputs found
Chemical Recycling of Carbon Dioxide to Methanol and Dimethyl Ether: From Greenhouse Gas to Renewable, Environmentally Carbon Neutral Fuels and Synthetic Hydrocarbons
PERSPECTIVE ON ELECTROCHEMICAL ENERGY CONVERSION IN FUTURE:5th JAPAN-USSR Seminar on Electrochemistry
Der Einfluß von Anionen und ihrer Konzentration auf die polarographische Reduktion von Sauerstoff
Mechanism of the electrooxidation of methanol on a smooth platinum electrode in alkaline solution
Palladium nanoparticles and nanowires deposited electrochemically: AFM and electrochemical characterization
Abstract Palladium nanoparticles and nanowires electrochemically deposited onto a carbon surface were studied using cyclic voltammetry, impedance spectroscopy and atomic force microscopy. The ex situ and in situ atomic force microscopy (AFM) topographic images showed that nanoparticles and nanowires of palladium were preferentially electrodeposited to surface defects on the highly oriented pyrolytic graphite surface and enabled the determination of the Pd nanostructure dimensions on the order of 50–150 nm. The palladium nanoparticles and nanowires electrochemically deposited onto a glassy carbon surface behave differently with respect to the pH of the electrolyte buffer solution. In acid or mild acid solutions under applied negative potential, hydrogen can be adsorbed/absorbed onto/into the palladium lattice. By controlling the applied negative potential, different quantities of hydrogen can be incorporated, and this process was followed, analysing the oxidation peak of hydrogen. It is also shown that the growth of the Pd oxide layer begins at negative potentials with the formation of a pre-monolayer oxide film, at a potential well before the hydrogen evolution region. At positive potentials, Pd(0) nanoparticles undergo oxidation, and the formation of a mixed oxide layer was observed, which can act as nucleation points for Pd metal growth, increasing the metal electrode surface coverage. Depending on thickness and composition, this oxide layer can be reversibly reduced. AFM images confirmed that the PdO and PdO2 oxides formed on the surface may act as nucleation points for Pd metal growth, increasing the metal electrode surface coverage
Variation in the EPR characteristics of nanosized zirconia particles under exposure to X-ray radiation and annealing in hydrogen
Study of the internal morphology of cation-exchange membranes by means of electroosmotic permeability relaxations.
The effect of an ac sinusoidal perturbation of known amplitude and frequency superimposed to the usual dc
applied electric voltage difference on the electroosmotic flow through three cation-exchange membranes with different morphology has been studied. A dispersion of the electroosmotic permeability on the frequency of the applied ac signal has been found for the three membranes investigated, observing that the electroosmotic permeability reaches maximum values for some characteristic values of the frequency. These characteristic frequency values, which are related to relaxation processes in heterogeneous media, depend on the membrane system and permit to obtain information about the different structures of the membrane system. Thus, the study of the electroosmotic permeability relaxation can be used as a method to study the internal morphology of a cation-exchange membrane in a given electrolyte medium
- …