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Hydrogen Desorption (hydrogen + desorption)
Selected AbstractsHow Carbon Affects Hydrogen Desorption in NaAlH4 and Ti-Doped NaAlH4.CHEMINFORM, Issue 31 2007C. Cento Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF. [source] Mixed-Anion and Mixed-Cation Borohydride KZn(BH4)Cl2: Synthesis, Structure and Thermal DecompositionEUROPEAN JOURNAL OF INORGANIC CHEMISTRY, Issue 11 2010Dorthe B. Ravnsbæk Abstract KZn(BH4)Cl2, synthesized for the first time, contains a heteroleptic complex anion [Zn(BH4)Cl2],, extending the structural diversity of metal borohydrides. In-situ synchrotron powder diffraction, NMR and Raman spectroscopy were used to characterize KZn(BH4)Cl2 and to evaluate the mechanism for its thermal decomposition. The title compound decomposes at a significantly lower temperature than KBH4 and may be used for inspiration for the design of novel hydrogen storage materials. Combining different ligands in modified metal borohydrides is proposed as a way to adjust stability with respect to hydrogen desorption. [source] Combustion-type hydrogenation of nanostructured Mg-based composites for hydrogen storageINTERNATIONAL JOURNAL OF ENERGY RESEARCH, Issue 13 2009M. V. Lototsky Abstract In this study Reactive Ball Milling in hydrogen gas was used to synthesize nanostructured hydrogenated composites of Mg and V-based alloy. After hydrogen desorption, the nanocomposites exhibited a dramatic facilitation of the rate of H absorption by Mg and reduction of the temperature of onset of hydrogenation. These favourable changes were caused by a synergy of catalytic effect of the V-based alloy on hydrogen absorption by Mg and heat release caused by exothermic hydrogen absorption by the V-based alloy. When the initial interaction temperature exceeded a threshold, rather low, value of 20,125°C, depending on the H2 pressure, composition of the sample and its total amount, a combustion-type hydrogenation took place. With optimal interaction parameters applied, H absorption was completed in just 5,70,s and was accompanied by a significant heat release. The observed features can be utilized to reach fast recharge of the Mg-based H stores and to develop efficient heat management systems. Copyright © 2009 John Wiley & Sons, Ltd. [source] Electron beam irradiation of porous silicon for application in micromachining and sensingPHYSICA STATUS SOLIDI (A) APPLICATIONS AND MATERIALS SCIENCE, Issue 8 2005S. Borini Abstract We have studied the effect of the electron beam (EB) irradiation on porous silicon (PS), in order to find new possibilities for the local modification of the material at the submicrometer scale. The interaction between the accelerated electrons and PS has been investigated by means of two main techniques: infrared spectroscopy and profilometric measurements. All the results show that a strong increase of reactivity is induced on PS surface under exposure to the EB, due to the hydrogen desorption provoked by the incident electrons. We demonstrate that this phenomenon can be exploited for both the lateral structuring and the local functionalization of PS, at the submicrometer scale, depending on the different treatments applied to the samples after the EB bombardment. (© 2005 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] Joint FTIR and TPD study of hydrogen desorption from p+ -type porous siliconPHYSICA STATUS SOLIDI (A) APPLICATIONS AND MATERIALS SCIENCE, Issue 1 2003P. Rivolo Abstract The H-terminated surface of Porous Silicon (PS) has been studied in the past decade basically by means of Fourier transform infrared (FTIR) spectroscopy. In one case only, a temperature programmed desorption (TPD) technique has been applied to an n-type PS sample. However, the evaluation of the amount of hydrogen thermally desorbed has never been attempted. The present work reports the joint FTIR and TPD study of hydrogen desorption from p+ -type PS and estimates the amount of hydrogen desorbed in the range 40,850 °C to be around 2 mmol/g. This suggests a ratio between H atoms and surface Si atoms of about one, giving support to the picture of PS as H-covered: as a consequence, only a few bare Si atoms are exposed at the surface and prone to act as adsorption centres, e.g. of NO2. A weak signal, in the TPD curve, is probably associated with the decomposition of a few Si,H,B bulk complexes. [source] | ||||||||||