INES - Innovative Energiespeicher auf der Basis von Kohlenstoffnanostrukturen Abschlussbericht

Abstract

Within the framework of the research project INES about 100 samples were investigated with respect to their morphology and short range order. Besides catalyst precursors especially carbon nanofibres as well as a few carbon nanotubes, aerogels and graphites have been investigated. In addition, the effect of modification processes of the structural features have been studied for selected carbon nanofibre, aerogel and graphite samples. All experimental techniques applied - except for REM-provide average values for the structural parameters. For the catalysts prepared the impact of the different synthesis methods used, i.e. conventional and microemulsion based precipitation of the carbonate precursors, on the short range order of the respective metal oxides have been quantified. The nanofibres characterized with respect to their morphology could be divided into four categories. For a given morphology the short range order, however, strongly varies with the fibre synthesis parameters, especially the catalyst composition, -synthesis and -preparation. The nanofibres provided by Rodriguez and Baker, Boston, USA, have been identified as spaghetti-like fibres with fishbone type arrangement of the graphene layers. The activation of the fibres prior to H_2-storage tests results - averaged over the sample - in a decrease of their short range order as well as their microporosity. Conclusions about the structural changes induced by activation, however, are due to the different carbon structures present in each batch only possible with additional information through TEM (DLR). The obtained reduction of the accessible inner surface through the passivation of samples for Li-storage could be well followed by combining small angle X-ray scattering and gas sorption analysis. (orig.)Available from TIB Hannover: F04B617 / FIZ - Fachinformationszzentrum Karlsruhe / TIB - Technische InformationsbibliothekSIGLEBundesministerium fuer Wirtschaft und Arbeit, Bonn (Germany)DEGerman