Thermodynamic optimization of the system magnesium–hydrogen

On the basis of our own calorimetric data and of known equilibria data the phase equilibria in the system Mg–H have been completely calculated by means of an optimization. Both for α-MgHx and MgH2 optimized free enthalpy functions are obtained

Innovative Energiespeichersysteme auf Basis von Polymeren Verbundstoffen und Kohlenstoffnanostrukturen fuer den mobilen Einsatz in Fahrzeugen und Elektronikgeraeten. Teilprojekt: Charakterisierung: Gravimetrische Bestimmung des Sorptionsverhaltens von Wasserstoff an Kohlenstoff-Nano-Fasern Schlussbericht

The development of a thermogravimetric apparatus for investigating the sorption and hydration characteristics of carbon nanofibres (SARTORIUS Supermikrowaage) is described.Berichtet wird ueber die Entwicklung einer thermogravimetrischen Apparatur zur Untersuchung des Sorptions- bzw. Hydrierverhaltens von Kohlenstoff-Nano-Fasern (SARTORIUS Supermikrowaage).Available from TIB Hannover: DtF QN1(112,38) / FIZ - Fachinformationszzentrum Karlsruhe / TIB - Technische InformationsbibliothekSIGLEBundesministerium fuer Bildung und Forschung, Berlin (Germany)DEGerman

An investigation of the effect of ti, pd and zr on the dehydriding kinetics of mgh2

The effect of additives Ti, Pd and Zr on the rate of hydrogen desorption from MgH2 is investigated using high-pressure differential scanning calorimetry. Van't Hoff analysis as well as X-ray powder diffraction measurements confirm that no new intermetallic phases are formed in these systems but enhanced dehydriding kinetics are obtained in the presence of Pd and Zr. For the Mg-Zr composite, Zr precipitates are formed throughout the material on heating to 500 °C but these do not grow with further thermal cycling. The desorption rate for all the composites was found to increase with temperature as well as pressure difference between experimental and equilibrium pressures. A value of 114 ± 4 kJ mol−1 was obtained for the activation energy for dehydriding of the Mg-Ti-Pd composite. The effect of additives Ti, Pd and Zr on the rate of hydrogen desorption from MgH2 is investigated using high-pressure differential scanning calorimetry. Van't Hoff analysis as well as X-ray powder diffraction measurements confirm that no new intermetallic phases are formed in these systems but enhanced dehydriding kinetics are obtained in the presence of Pd and Zr. For the Mg-Zr composite, Zr precipitates are formed throughout the material on heating to 500 °C but these do not grow with further thermal cycling. The desorption rate for all the composites was found to increase with temperature as well as pressure difference between experimental and equilibrium pressures. A value of 114 ± 4 kJ mol−1 was obtained for the activation energy for dehydriding of the Mg-Ti-Pd composite