Hydrogen Uptake and Release in Carbon Nanotube Electrocatalysts

The recent technique of molecular beam-thermal desorption spectrometry was used here for monitoring hydrogen uptake and release from carbon nanotube networks, after electrochemical hydrogen uptake. This way, an accurate determination of the hydrogen mass absorbed in electrodes made from those assemblies can be achieved by significantly improving the signal-to-noise ratio. The hydrogen desorption mass spectra account for the enhanced surface capability for hydrogen adsorption in the electrodes and enable a comparison with the performance of a palladium electrode in similar conditions. A comparative study involving different carbon nanotube electrodes, in similar hydrogen uptake/desorption conditions, clearly confirmed the expectations about their enhanced hydrogen storage capacity and points to the great potential of carbon nanotube assemblies in replacing the heavier metal alloys as electrocatalysts.

Исследование быстродействия поверхностно-ионизационных детекторов

This paper presents the results of the studies obtained by the method of thermal desorption spectrometry, aimed at studying the dependence of the speed of the surface ionization detector on the temperature (Te) of the emitter. For this purpose, the detector recorded the evaporation spectra of heroin, papaverine and morphine, obtained at different rates of temperature-programmed heating of substances. To study the dependence of the speed of the detectors on the emitter Te, these spectra were obtained at different emitters Te. It was revealed that with an increase in the emitter Te, the response speed of the detector increases. This increase is associated with an increase in the rates of heterogeneous processes in the adsorption layer of the emitter with increasing Te. A mathematical model was developed for this dependence, based on surface ionization of molecules under non-stationary conditions.

Decomposition of nitric oxide by rhodium cluster cations at high temperatures

Decomposition reactions of NO molecules on gas-phase Rhn+ (n = 6–9) clusters were investigated by gas-phase thermal desorption spectrometry and density functional theory calculations. We found that NO adsorbs on...

DEUTERIUM TRAPPING IN TUNGSTEN IRRADIATED WITH DEUTERIUM PLASMA AT HIGH TEMPERATURES

This work was attended to the study of the accumulation of deuterium, also to the investigation of the process of capture of deuterium in tungsten samples upon irradiation with a plasma beam. It was shown that after irradiation on the surface, a change in the surface is observed as the development of the relief as a result of nonuniform etching of the surface. The degree of change in the relief and structure of the surface layer of the irradiated samples depends on the irradiation temperature. The accumulation of deuterium tungsten under irradiation with deuterium plasma was studied. The conducted thermal desorption analysis of tungsten samples irradiated with deuterium plasma showed that the tungsten surface is saturated with deuterium. The data obtained by the method of emission spectrometry and thermal desorption spectrometry showed that the majority of the captured deuterium accumulates at a depth under the 7 μm.

Effect of atomicity on the oxidation of cationic copper clusters studied using thermal desorption spectrometry

The resistivity to oxidation of small copper clusters, Cun+ (n ≤ 5), in the gas phase with a precise atomicity at the molecular level was investigated using a combination of thermal desorption spectrometry and mass spectrometry.