Platinum nanoparticles dispersed on nanosized ceria are active for CO oxidation at room temperature after hydrogen pretreatment. High angular annular dark field scanning transmission electron microscopy (HAADF-STEM) analysis of the reduced catalyst shows spreading of the 1 nm sized platinum particles under the electron beam, characteristic for a two-dimensional strong metal–support interaction. In situ X-ray absorption fluorescence spectroscopy (XAFS) reveals a Pt–O distance of 2.1 Å, which is significantly longer than the Pt–O distance in PtO2 (2.0 Å). This elongated Pt–O distance can be related to interaction of the platinum species with cerium oxide in the form of a low-temperature active species–support interaction. These findings contribute to the general understanding of catalytic systems operating at low temperature.

BM23 is the general-purpose EXAFS bending-magnet beamline at the ESRF, replacing the former BM29 beamline in the framework of the ESRF upgrade. Its mission is to serve the whole XAS user community by providing access to a basic service in addition to the many specialized instruments available at the ESRF. BM23 offers high signal-to-noise ratio EXAFS in a large energy range (5-75 keV), continuous energy scanning for quick-EXAFS on the second timescale and a micro-XAS station delivering a spot size of 4 mm  4 mm FWHM. It is a user-friendly facility featuring a high degree of automation, online EXAFS data reduction and a flexible sample environment.

Using a simple slow decomposition method of nitrate precursors, high-surface area platinumdoped ceria with a crystallite size of 9 nm can be prepared. The catalytic performance of the compound can be tuned by changing the reduction temperature under hydrogen (300°C, 500°C and 700°C). The catalyst treated at 300°C shows the best catalytic performance, being active at room temperature. The materials were analysed using a combination of structural characterization methods (X-ray diffraction (XRD), nitrogen physisorption, high angle annular dark field scanning transmission electron microscopy (HAADF-STEM)), surface sensitive methods (X-ray photoelectron spectroscopy (XPS), H 2-chemisorption and H 2temperature-programmed reduction (TPR)) and X-ray absorption fluorescence spectroscopy (XAFS). HAADF-STEM and XAFS analysis suggests successful doping of platinum in the ceria lattice. After pretreatment at 300°C, the situation is slightly different. While no defined platinum nanoparticles can be identified on the surface, some platinum is in a reduced state (XPS, H 2-chemisorption).

The effect of the co‐components Mn, Co, Au, and Sb with a wide range of standard reduction potentials (Mn2+/Mn: E°=−1.18 V; Co2+/Co: E°=−0.28 V; Sb3+/Sb: E°=+0.2 V; Au3+/Au: E°=+1.52 V) on the catalytic performance of 10 wt % Pd, 8 wt % M/TiO2 (M=Mn, Co, Sb, Au) catalysts in the gas‐phase acetoxylation of toluene to benzyl acetate has been studied. Co‐components with low E° are more active, but less selective than those with high E°. Co‐components with low E° (Mn, Co) stabilize Pd in its oxidized form, whereas those with high E° (Sb, Au) support the formation of metallic Pd. Sb and Au are incorporated into the Pd lattice, whereas Mn and Co are enriched at the surface during time on stream. Carbon is deposited on all catalysts during the reaction. However, for Mn‐ and Co‐containing catalysts, carbon is incorporated into the metal particles, whereas it is deposited on top of Pd particles modified with Sb and Au, which leads to faster deactivation.

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