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Title: Facile Synthesis of Ceria Nanocrystals with Tuneable Size and Shape
Abstract Ceria (CeO 2 ) possesses a distinctive redox property due to a reversible conversion to its nonstoichiometric oxide and has been considered as a promising catalyst in the oxidative coupling of methane. Since a heterogeneously catalytic process usually takes place only on the surface of catalysts, it is reasonably expected that the performance of a catalyst, such as CeO 2 , highly relies on its size- and shape-dependent surface structure. We report our recent progress in achieving exclusive crystal facet-terminated CeO 2 nanocrystals using a shape-controlled synthesis protocol in a one-pot colloidal system. We modified a two-phase solvothermal approach to fabricate cubic and truncated octahedral CeO 2 nanocrystals with a size-control. During the two-phase solvothermal process, we propose that the Ce-precursors transfer from the aqueous layer to the interface of the organic phase, promoted by the capping ligands (as known as phase-transfer catalysts), for the oxidation and nucleation, and subsequently form CeO 2 nanocrystals in the organic layer. As different capping ligands favor binding on diverse crystal facets, tuning the composition of the capping ligand with a precise control could generate nanocrystals that are dominated by a single type of facets with a relatively narrow size distribution.  more » « less
Award ID(s):
1808383
PAR ID:
10166597
Author(s) / Creator(s):
; ; ; ; ;
Date Published:
Journal Name:
MRS Advances
Volume:
5
Issue:
11
ISSN:
2059-8521
Page Range / eLocation ID:
523 to 529
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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