Papers by Author: Hong Seok Chin

Abstract: With the aim of replacing Pd coating layer currently used for the dissociation and recombination of hydrogen molecules, the performance of Nb and Ta thin layers as catalystforhydrogen permeationwas evaluated at 673 K.Although not as efficient as Pd, Nb and Ta coating layers can nevertheless provide a reasonable H2 dissociation and recombination rates. Thereduced values of hydrogen permeabilityin comparison to that of Pd were explained by the reduced catalytic properties of Nb and Ta and the formation of hydrides on the surface.

Abstract: The hydrogen permeation properties of the Pd-coated Ni37.5Nb27.5Zr25Co5Ta5 amorphous membranes have been investigated at 673 and 723K for 720 hours (1 month). Values of the hydrogen permeability during these long term tests were found to be reduced of about 50 and 30 % at 673 and 723K, respectively. The reduction in the hydrogen permeability could be correlated to the change in the composition of the coating as well as at the interface between Pd coating and Ni-based amorphous membrane.