In-situ X-ray Spectroscopy
Structural selectivity of supported Pd nanoparticles for catalytic NH3 oxidation resolved using combined operando spectroscopy
The link between Pd nanoparticle structure and surface reactivity for NH3 abatement was found using operando X-ray absorption fine structure spectroscopy, diffuse reflectance infrared Fourier-transformed spectroscopy and on-line mass spectrometry.
Kinetics of Lifetime Changes in Bimetallic Nanocatalysts Revealed by Quick X‐ray Absorption Spectroscopy
The different reaction steps involved in repeated Pt13In9 segregation‐alloying are identified by XAS and kinetically characterized at the single‐cycle level.
The highest award of the international X-ray absorption spectroscopy (IXAS) society, the Edward Stern Outstanding Achievement Award, was presented to Prof. Ronald Frahm during the tri-annual IXAS meeting in Kraków, Poland in July 2018.
Structure of the Co(I) Intermediate of a Cobalt Pentapyridyl Catalyst for Hydrogen Evolution Revealed by Time‐Resolved X‐ray Spectroscopy
The mechanism of hydrogen evolution by cobalt polypyridyls catalysts is investigated. Pump-probe X‐ray absorption spectra measured at SuperXAS in the microsecond time range indicate that the pendant pyridine dissociates from the cobalt in the intermediate Co(I) state. This opens the possibility for pyridinium to act as an intramolecular proton donor, which can be used for the development of efficient catalysts.
Using targeted synthesis and in situ characterization a palladium catalyst with improved stability against sintering during methane oxidation was prepared.
Combining SAXS and XAS To Study the Operando Degradation of Carbon-Supported Pt-Nanoparticle Fuel Cell Catalysts
In the last two decades, small-angle X-ray scattering (SAXS) and X-ray absorption spectroscopy (XAS) have evolved into two well-established techniques capable of providing complementary and operando information about a sample’s morphology and composition, respectively. Considering that operation conditions can often lead to simultaneous and related changes in a catalyst’s speciation and shape, herein we introduce a setup that combines SAXS and XAS in a configuration that allows optimum acquisition and corresponding data quality for both techniques.
Through the combination of time-resolved X-ray absorption spectroscopy and transient experimentation, we were able to capture an ammonia inhibition effect on the rate-limiting copper re-oxidation at low temperature.
Using a unique set of well-defined silica-supported Ni nanoclusters (1–7 nm) and advanced characterization methods it was proved how structure sensitivity influences the mechanism of catalytic CO2 reduction, the nature of which has been long debated.
By combining a scalable cutting-edge synthesis method with time-resolved X-ray absorption spectroscopy measurements, it was possible to capture the dynamic local electronic and geometric structure during realistic operando conditions for highly active OER perovskite nanocatalysts.