10.1021/jp505433a.s001
Junjie Shi
Junjie
Shi
Andreas Schaefer
Andreas
Schaefer
Andre Wichmann
Andre
Wichmann
M. Mangir Murshed
M. Mangir
Murshed
Thorsten
M. Gesing
Thorsten
M.
Gesing
Arne Wittstock
Arne
Wittstock
Marcus Bäumer
Marcus
Bäumer
Nanoporous
Gold-Supported Ceria for the Water–Gas Shift Reaction: UHV
Inspired Design for Applied Catalysis
American Chemical Society
2014
metal oxide deposits
stability
npAu disks
Raman spectroscopic characterization
WGS reaction
flow reactor
model studies
Cerium oxide deposits
cerium oxide deposits
CO 2
ultrahigh vacuum
UHV
cerium nitrate precursor
H 2O
15 h
gold material
ambient pressure conditions
Applied CatalysisInspired
nanosized gold ligaments
nanoporous gold
2014-12-18 00:00:00
Journal contribution
https://acs.figshare.com/articles/journal_contribution/Nanoporous_Gold_Supported_Ceria_for_the_Water_Gas_Shift_Reaction_UHV_Inspired_Design_for_Applied_Catalysis/2224192
Inspired by model studies under ultrahigh
vacuum (UHV) conditions, inverse monolithic gold/ceria catalysts are
prepared using thermal decomposition of a cerium nitrate precursor
on a nanoporous gold (npAu) substrate. Cerium oxide deposits throughout
the porous gold material (pores and ligaments 30–40 nm) are
formed. npAu disks and coatings were prepared with loadings of about
3 to 10 atom % of ceria. The composite material was tested for the
water–gas shift (WGS) reaction (H<sub>2</sub>O + CO →
H<sub>2</sub> + CO<sub>2</sub>) in a continuous flow reactor at ambient
pressure conditions. Formation of CO<sub>2</sub> was observed at temperatures
as low as 135 °C with excellent stability and reproducibility
up to temperatures of 535 °C. The considerably increased thermal
stability of the material can be linked to the presence of metal oxide
deposits on the nanosized gold ligaments. The loss of activity after
about 15 h of catalytic conversion with heating to 535 °C was
only about 10%. Photoemission spectroscopy indicates a defect (Ce<sup>3+</sup>) concentration of about 70% on the surface of the cerium
oxide deposits, prior to and after WGS reaction. Raman spectroscopic
characterization of the material revealed that the bulk of the oxide
is reoxidized during reaction.