Changes of Phase Composition of NaAlH4 Based Complex Hydrides

0374448 - ÚFM 2012 RIV CZ eng C - Konferenční příspěvek (zahraniční konf.)
Roupcová, Pavla - Schneeweiss, Oldřich
Changes of Phase Composition of NaAlH4 Based Complex Hydrides.
NANOCON 2011. Conference Proceedings. Ostrava: Tanger Ltd, 2011, s. 726-729. ISBN 978-80-87294-23-9.
[NANOCON 2011. International Conference /3./. Brno (CZ), 21.09.2011-23.09.2011]
Grant CEP: GA MŠMT 1M0512; GA MŠMT(CZ) ED1.1.00/02.0068; GA ČR GP106/09/P556
Výzkumný záměr: CEZ:AV0Z20410507
Klíčová slova: Mössbauer spectroscopy * hydrogen absorbing materials
Kód oboru RIV: BM - Fyzika pevných látek a magnetismus

The Mössbauer study is target to valence of Fe-doped phase and its changes during preparation by mixing with NaAlH4 and charging and discharging cycles. The 2 mol % FeCl2·4H2O powder was contained in the asmixing material. The dry milled sample did not transformed during the milling in the protective atmosphere. The significant change was approved in the firstly hydrogenation step only. The analysis shows FeClO which released the most significant component in the dehydrogenation and hydrogenation steps. The amount of FeClO was decreased with the all following step of hydrogenation and dehydrogenation. The fine paramagnetic particles of iron oxides were detected and their amount increased influenced of gas impurities. The longer period of heat treatment shows the agglomeration of iron oxides and their magnetic effect.
Trvalý link: http://hdl.handle.net/11104/0207366