نتایج جستجو برای: hydrogen adsorption
تعداد نتایج: 197034 فیلتر نتایج به سال:
Hydrogen storage is one of the most addressed issues in the green-economy field. The latest-discovered form of ice (XVII), obtained by application of an annealing treatment to a H2-filled ice sample in the C0-phase, could be inserted in the energy-storage context due to its surprising capacity of hydrogen physisorption, when exposed to even modest pressure (few mbars at temperature below 40 K),...
The adsorption and hydrogenation of methyl iodide is studied on clean and hydrogen-covered Pd(1 1 1) using reflection–adsorption infrared spectroscopy (RAIRS) and temperature-programmed desorption. Molecular methyl iodide desorbs from clean Pd(1 1 1) at 229 K and hydrogen desorbs at 360 K. Methyl groups hydrogenate in two states at 191 and 304 K for large methyl iodide exposures where RAIRS dat...
We report the first six-dimensional quantum dynamical calculations of dissociative adsorption and associative desorption. Using a potential energy surface obtained by density functional theory calculations, we show that the initial decrease of the sticking probability with increasing kinetic energy in the system H2/Pd(100), which is usually attributed to the existence of a molecular adsorption ...
Hydrogen storage and release are two essential parameters that define the efficiency of a hydrogen storage medium. Herein, we investigate the effects of the external electric field F on the adsorption-desorption of H2 on a Ca-decorated silicene system (Ca-silicene) based on density functional theory calculations. Our study demonstrates that nine H2 molecules per Ca atom can be adsorbed and 6.4 ...
Sabatier's principle suggests, that for hydrogen evolution a plot of the rate constant versus the hydrogen adsorption energy should result in a volcano, and several such plots have been presented in the literature. A thorough examination of the data shows, that there is no volcano once the oxide-covered metals are left out. We examine the factors that govern the reaction rate in the light of ou...
Carbon single-wall nanotubes (SWNTs) are capable of adsorbing hydrogen quickly, to high density, at ambient temperatures and pressures. Last year, we showed that hydrogen storage densities on SWNTs made by laser vaporization ranged from 3.5 to 4.5 wt% after a cutting procedure was performed. We present details of the cutting procedure here and show that, when optimized, hydrogen storage densiti...
The adsorption/absorption of hydrogen at room temperature by palladium, 16% silver-palladium and 5% ruthenium-palladium foils was studied using thermal desorption spectroscopy. Hydrogen readily diffused in the palladium and desorbed as one broad peak at about 650 K. Hydrogen also diffuses in the 16% silver-palladium foil and in the 5% rutheniumpalladium foil but with a smaller diffusion constan...
The indium phosphide (001) surface provides a unique chemical environment for studying the reactivity of hydrogen toward the electron-deficient group IIIA element, indium. Hydrogen adsorption on the In-rich delta(2 x 4) reconstruction produced a neutral, covalently bound bridging indium hydride. Using vibrational spectroscopy and ab initio cluster calculations, two types of bridging hydrides we...
The interaction of methanol with a clean <I 10) ruthenium surface has been studied using temperature programmed desorption methods. Methanol dissociates upon adsorption at 300 K and yields Ha(g) and chemisorbed CO as the domiwt products. Randomization of evolved hydrogen was shown to occur during methanol adsorption and also upon subsequent thermal desorption using isotopically labeled methanol...
Calcium carbonate/cellulose fiber composites combining natural polymers and inorganic particles are promising materials for preparing fluff pulp. In this study, calcium carbonate (CaCO3) particles were in-situ precipitated on cellulose fiber surfaces to decrease the level of hydrogen bonding. The results showed that nano CaCO3 particles precipitated and dispersed well on the fiber surface. The ...
نمودار تعداد نتایج جستجو در هر سال
با کلیک روی نمودار نتایج را به سال انتشار فیلتر کنید