Surface chemistry, structure, and reactivity
of multi-component spinel nanoparticles

Subproject P10

Multi-component spinel oxides are complex materials. Understanding their properties and reactivity is challenging, even more so when considering defect-rich nanoparticles under actual reaction conditions.

In P10, we will apply a comprehensive, multi-technique operando approach to investigate Fe-based spinel oxide nanoparticles used as WGS and oxidation catalysts in the gas and liquid phase. We will determine their surface composition, particularly under reaction conditions, the state, coordination environment, and role of the constituent cations, and the influence of defects. We will link these properties to the reactivity and interaction with O2, H2O, H2, CO, and CO2. Furthermore, we will evaluate how spinels and their surfaces change when exposed to the liquid phase. Our experimental approach comprises synthesis, characterization (TEM, XRD, XPS, TPD, titration of sites and defects, IR of probe molecules), steady-state and transient kinetics, and operando characterization (IR, NAP-XPS, XAS).

In close interaction with surface science (P04 Parkinson), we will compare the nanoparticulate materials to single-crystal and thin-film model systems. For understanding complex materials, a close collaboration with the surface science and theory groups is essential. In return, our results on technologically relevant nanoparticles under operation conditions will help to validate and adapt models and address the influence of high defectivity, low coordinated sites, disorder, and low crystallinity. We aim to bridge fundamental theory studies, surface science experiments, and model studies (P11 Backus) towards real-world application.

Karin Föttinger
PI

Expertise

Our group has long term experience in the application of operando spectroscopy (FTIR, XPS and XAS) for studying heterogeneous catalysts. Our research interests are centered around establishing structure-performance relations of oxides and supported metal nanoparticles and identifying reaction mechanisms. Understanding the elementary reaction steps occurring at the catalyst surface and identification of the involved intermediates and surface sites under relevant conditions is a main focus and crucial for a rational design and improvement of catalytic materials.

Methods and expertise available in our lab include:

  • in situ/operando FTIR (transmission, DRIFTS and ATR-IR) during catalytic reactions (steady-state and concentration modulation setups)
  • several laboratory-scale flow reactors equipped with gas chromatographs and mass spectrometers for performing catalytic reactions in the gas and liquid phase
  • in-situ Near Ambient Pressure XPS setup
  • volumetric physisorption and chemisorption, dynamic (pulsed) chemisorption
  • temperature-programmed methods (TPD, TPR, TPO)
  • DR-UV/VIS spectroscopy
  • thermal analysis (DSC and TGA)
  • fully equipped synthesis lab
  • we regularly perform in situ XAS and high resolution XRD/total scattering at synchrotron facilities using dedicated operando cells
  • we frequently utilize HR-TEM with EDX and EELS, SEM, XRF, XRD (including in situ XRD) and ICP-MS available via service centers and/or collaborations

Team

Karin Föttinger
PI

Christoph Rameshan
co-PI

Michael Pittenauer
PhD

Publications

2020

Interplay between CO Disproportionation and Oxidation: On the Origin of the CO Reaction Onset on Atomic Layer Deposition-Grown Pt/ZrO2 Model Catalysts

Pramhaas, Verena; Roiaz, Matteo; Bosio, Noemi; Corva, Manuel; Rameshan, Christoph; Vesselli, Erik; Grönbeck, Henrik; Rupprechter, Günther

Interplay between CO Disproportionation and Oxidation: On the Origin of the CO Reaction Onset on Atomic Layer Deposition-Grown Pt/ZrO2 Model Catalysts Journal Article

In: ACS Catalysis, 11 (1), pp. 208–214, 2020.

Abstract | Links | BibTeX | Tags: P08, P10, pre-TACO

An ultrahigh vacuum-compatible reaction cell for model catalysis under atmospheric pressure flow conditions

Haunold, Thomas; Rameshan, Christoph; Bukhtiyarov, Andrey V; Rupprechter, Günther

An ultrahigh vacuum-compatible reaction cell for model catalysis under atmospheric pressure flow conditions Journal Article

In: Review of Scientific Instruments, 91 (12), pp. 125101, 2020.

Abstract | Links | BibTeX | Tags: P08, P10, pre-TACO

Modifying the Surface Structure of Perovskite-Based Catalysts by Nanoparticle Exsolution

Lindenthal, Lorenz; Rameshan, Raffael; Summerer, Harald; Ruh, Thomas; Popovic, Janko; Nenning, Andreas; Löffler, Stefan; Opitz, Alexander Karl; Blaha, Peter; Rameshan, Christoph

Modifying the Surface Structure of Perovskite-Based Catalysts by Nanoparticle Exsolution Journal Article

In: Catalysts, 10 (3), pp. 268, 2020.

Abstract | Links | BibTeX | Tags: P10, pre-TACO

2018

Operando Insights into CO Oxidation on Cobalt Oxide Catalysts by NAP-XPS, FTIR, and XRD

Lukashuk, Liliana; Yigit, Nevzat; Rameshan, Raffael; Kolar, Elisabeth; Teschner, Detre; Hävecker, Michael; Knop-Gericke, Axel; Schlögl, Robert; Föttinger, Karin; Rupprechter, Günther

Operando Insights into CO Oxidation on Cobalt Oxide Catalysts by NAP-XPS, FTIR, and XRD Journal Article

In: ACS Catalysis, 8 (9), pp. 8630–8641, 2018.

Abstract | Links | BibTeX | Tags: P08, P10, pre-TACO

2016

Operando XAS and NAP-XPS studies of preferential CO oxidation on Co3O4 and CeO2-Co3O4 catalysts

Lukashuk, Liliana; Föttinger, Karin; Kolar, Elisabeth; Rameshan, Christoph; Teschner, Detre; Hävecker, Michael; Knop-Gericke, Axel; Yigit, Nevzat; Li, Hao; McDermott, Eamon; Stöger-Pollach, Michael; Rupprechter, Günther

Operando XAS and NAP-XPS studies of preferential CO oxidation on Co3O4 and CeO2-Co3O4 catalysts Journal Article

In: Journal of Catalysis, 344 , pp. 1–15, 2016.

Abstract | Links | BibTeX | Tags: P08, P10, pre-TACO

Methane dry reforming over ceria-zirconia supported Ni catalysts

Wolfbeisser, Astrid; Sophiphun, Onsulang; Bernardi, Johannes; Wittayakun, Jatuporn; Föttinger, Karin; Rupprechter, Günther

Methane dry reforming over ceria-zirconia supported Ni catalysts Journal Article

In: Catalysis Today, 277 , pp. 234–245, 2016.

Abstract | Links | BibTeX | Tags: P08, P10, pre-TACO

2014

In Situ Spectroscopy of Complex Surface Reactions on Supported Pd–Zn, Pd–Ga, and Pd(Pt)–Cu Nanoparticles

Föttinger, Karin; Rupprechter, Günther

In Situ Spectroscopy of Complex Surface Reactions on Supported Pd–Zn, Pd–Ga, and Pd(Pt)–Cu Nanoparticles Journal Article

In: Accounts of Chemical Research, 47 (10), pp. 3071–3079, 2014.

Abstract | Links | BibTeX | Tags: P08, P10, pre-TACO