Publication

In situ spectroscopic studies of the effect of water on the redox cycle of Cu ions in Cu-SSZ-13 during selective catalytic reduction of NOx

Publications associées (32)

The simultaneous Selective Catalytic Reduction of N2O and NO over Fe-exchanged zeolites

Iron-exchanged zeolites are industrial heterogeneous catalysts deployed to remediate anthropogenic emissions of both nitrous oxide (N2O) and nitrogen oxides (NOx = NO + NO2). Despite the extensive scientific attention received, limited knowledge is availab ...

EPFL2024

New Applications of 1,3,2-Diazaphospholenes in Catalysis

Johannes Klett

The constant urge to construct new molecules in an economical and sustainable fashion led to the development of numerous metal-catalyzed transformations. Organocatalysts consisting of abundant and more sustainable elements offer an elegant solution to over ...

EPFL2024

Assessing the effect of O2 dithering on CH4 oxidation on Pd/Al2O3

Oliver Kröcher, Davide Ferri

Under periodic lean/rich operation generated by repeated O2 pulses (O2-dithering), the abatement of CH4 and NO is enhanced compared to static operation. However, it is not well understood how the dithering parameters (pulse amplitude and frequency) affect ...

ELSEVIER SCIENCE SA2023

An Overview of Heterogeneous Catalysts Based on Hypercrosslinked Polystyrene for the Synthesis and Transformation of Platform Chemicals Derived from Biomass

Lioubov Kiwi

Platform chemicals, also known as chemical building blocks, are substances that serve as starting materials for the synthesis of various value-added products, which find a wide range of applications. These chemicals are the key ingredients for many fine an ...

MDPI2023

Monomeric Fe Species in Square Planar Geometry Active for Low Temperature NH3-SCR of NO

Oliver Kröcher, Davide Ferri

Monomeric Fe species in zeolites are considered to be the active sites for the low temperature activity toward ammonia-assisted selective catalytic reduction of nitrogen oxides (NH3-SCR) in exhaust gases. Herein, we report on a preparation method to synthe ...

AMER CHEMICAL SOC2022

One-pot synthesis of highly dispersed mesoporous Cu/ZrO2 catalysts for NH3-SCR

Oliver Kröcher, Davide Ferri, Rob Jeremiah G. Nuguid

Catalysts consisting of highly dispersed copper on a mesoporous ZrO2 support were synthesised via a one-pot sol-gel synthesis and were tested for the selective catalytic reduction of NOx by NH3. The copper dispersion was investigated by XRD and TEM, which ...

ELSEVIER2022

Emission reduction by targeted transient operations in three-way catalysts for heavy-duty natural gas applications

Moyu Wang

To curb the severe effects of climate change, our society needs to radically reduce its CO2 footprint. For the heavy-duty sector, where electrification is difficult, alternative fuels can be the solution. Methane-fueled engines have lower energy-specific C ...

EPFL2022

In Situ Infrared Spectroscopy of NOx Reduction Catalysts: A Laboratory Exercise for In-Person and Virtual Learning

Oliver Kröcher, Davide Ferri, Rob Jeremiah G. Nuguid

Infrared (IR) spectroscopy and catalysis represent two of the most practically relevant topics in chemistry, but they are normally taught in separate contexts at the undergraduate level. Although IR spectroscopy is introduced to students as a tool for orga ...

AMER CHEMICAL SOC2022

Aging of industrial Fe-zeolite based catalysts for nitrous oxide abatement in nitric acid production plants

Oliver Kröcher, Davide Ferri, Filippo Buttignol, Pierdomenico Biasi

The influence of hydrothermal aging on the structural and catalytic properties of two commercial Fe-exchanged zeolite catalysts (Fe-FER and Fe-ZSM-5) in the extruded form employed for the removal of N2O from the exhaust of nitric acid production plants has ...

ROYAL SOC CHEMISTRY2022

Stability and Reactivity of a Polyoxymethylene Dimethyl Ether over Typical Catalysts for Diesel Emission Control

Oliver Kröcher, Davide Ferri

Polyoxymethylene dimethyl ethers (OME) produced from methanol are considered as potential substitutes of Diesel fuel. Emissions of formaldehyde and other components have been observed, particularly under cold-start conditions in engine test-bench experimen ...

SPRINGER/PLENUM PUBLISHERS2023

Revisiting the Impact of Morphology and Oxidation State of Cu on CO2 Reduction Using Electrochemical Flow Cell

Michael Graetzel, Shaik Mohammed Zakeeruddin, Dan Ren, Jing Gao

Electroreduction of carbon dioxide (CO2) in a flow electrolyzer represents a promising carbon-neutral technology with efficient production of valuable chemicals. In this work, the catalytic performance of polycrystalline copper (Cu), Cu2O-derived copper (O ...

AMER CHEMICAL SOC2022

Hydro-processing of biomass using novel metal-organic framework (MOF)/polymer composite catalysts

Vikram Vinayak Karve

Generating value, in the form of functional chemicals, from biomass is a critical need of today. It is expected that replacing petroleum with biomass as the source of many commodity and fine chemicals can lead the transition away from a fossil-fuel based e ...

EPFL2022

Poisoning of Mn-Ce/AC catalysts for low-temperature NH3-SCR of NO by K+ and its counter-ions (Cl- /NO3- /SO42- )

Oliver Kröcher, Jie Yang, Davide Ferri, Rob Jeremiah G. Nuguid

Mn-Ce/AC catalysts for low-temperature NH3-SCR of NOx were deliberately loaded with various potassium salts (KCl, KNO3, and K2SO4) to investigate the influence of the counter-ions on the poisoning impact. Whereas K salts poisoning had only marginal impact ...

ELSEVIER2022

Highly Ordered and Thermally Stable FeRh Cluster Superlattice on Graphene for Low-Temperature Catalytic CO Oxidation

Harald Brune, Jean-Guillaume De Groot, Hao Yin

We report on bimetallic FeRh clusters with a narrow size-distribution grown on graphene on Ir(111) as a carbon-supported model catalyst to promote low-temperature catalytic CO oxidation. By combining scanning tunneling microscopy with catalytic performance ...

WILEY-V C H VERLAG GMBH2022

Investigation on the Role of Pd, Pt, Rh in Methane Abatement for Heavy Duty Applications

Oliver Kröcher, Davide Ferri, Moyu Wang

Methane abatement remains a challenge in aftertreatment systems of natural gas engines, currently under discussion in combination with synthetic methane. In this study, Pt/Rh and Pd/Rh-based three-way catalysts are investigated under various transient cond ...

MDPI2022

Understanding the impact of poison distribution on the performance of Diesel oxidation catalysts

Oliver Kröcher, Davide Ferri

Detailed understanding of the poisoning mechanism in Diesel oxidation catalysts (DOCs) is the key to prevent long term catalyst deterioration in vehicles. The present work studies artificial phosphorus (P) poisoning methods applied to a commercial DOC. Cor ...

ELSEVIER2021

On the relevance of P poisoning in real-world DOC aging

Oliver Kröcher, Davide Ferri

Understanding the real aging of Diesel oxidation catalysts (DOC) is key to predict their useful lifetime. This work comprises a detailed study of a commercial DOC in its unused state and after use in vehicle for 288,000 km. The activity of the samples was ...

ELSEVIER2021

HCN production from formaldehyde during the selective catalytic reduction of NOx with NH3 over V2O5/WO3-TiO2

Oliver Kröcher, Davide Ferri, Rob Jeremiah G. Nuguid

Raw exhaust gases may contain notable levels of formaldehyde that can negatively impact the efficiency of after -treatment systems. In the selective catalytic reduction (SCR) of NOx over V2O5/WO3-TiO2, formaldehyde was found to react with NH3 to produce HC ...

ELSEVIER2021

Time-Resolved Spectroscopy of Selective Catalytic Reduction (SCR) Catalysts under Transient Conditions

Rob Jeremiah G. Nuguid

Understanding the mechanisms behind chemical transformations is key to developing improved catalytic systems. To this end, operando spectroscopy has contributed significantly to the advancement of our molecular view of many reactions at the heart of the ch ...

EPFL2021

The Genesis of Molecular Volcano Plots

Anne-Clémence Corminboeuf, Matthew Wodrich, Michael Markus Busch, Boodsarin Sawatlon

For the past two decades, linear free energy scaling relationships and volcano plots have seen frequent use as computational tools that aid in understanding and predicting the catalytic behavior of heterogeneous and electrocatalysts. Based on Sabatier's pr ...

2021