Bein, Thomas; McLain, S. J.; Stucky, Galen D.; Woolery, G.; Sayers, D. E.; Möller, Karin
EXAFS study of nickel tetracarbonyl and nickel clusters in zeolite Y.
In: Journal de Physique, Colloque C8, Suppl. 12, Vol. 47: pp. 277-280
Adsorption and thermal decomposition of Ni(CO)4 in the cage system of zeolite Y
have been studied with EXAFS, electron microscopy and IR spectroscopy , Ni(CO)4
is adsorbed as an intact molecule in both cation - free zeolite Y and NaY. Symmetry
changes of the molecule in NaY are assigned to the formation of Na—OC-IMi bridges.
Thermal treatment of the Ni(CO)4/NaY adduct leads to loss of CO concomitant with
the formation of a binodal Ni phase. A major part of the forms clusters with
diameter between 0.5 and about 1.5 nm, in addition to larger crystallites
(5-30 nm), sticking at the outer surface of the zeolite matrix.,
The Ni-Ni scattering amplitude indicates increasing average particle size with