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more faceted ones.18 If these low coordination number corner
and/or edge positions are implicated as active sites for AB
dehydrogenation, then their relatively higher occurrence in the
PdNPs generated in this study could account for their superior
catalytic performance.
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During the course of the reactions, the activity of the PdNPs
was observed to decrease. After catalytic dehydrogenation, a
visible layer appeared to coat the catalyst. This coating was
removed by simple immersion in methanol and the PdNPs
retrieved from the solvent exhibited close to their original
catalytic activity, which was sustainable up to the tenth cycle
without any discernible catalytic loss (Table S1, ESIw).
11B NMR analysis of the spent fuels in TG indicated the
initial formation (after 5 min) of cyclic intermediates, as
identified by Sneddon12 and Shaw et al.19 (Fig S6, ESIw).
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confirmed the simultaneous decay of these signals and the
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This work is supported by the Basic Science Research Program
through the National Research Foundation of Korea (NRF)
funded by the Ministry of Education, Science and Technology
(No. 2011-0018595). This research was performed in collabora-
tion with the Hydrogen Energy R&D Center, which was funded
by the 21st Century Frontier R&D Program of MEST.
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Notes and references
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