essential for the majority of all chemical processes in industry. In
addition, they find numerous applications in refineries and in energy
conversion, and they help to protect the environment.
Nevertheless, their discovery and their optimization has often been
based on trial
and error, and there are only a few cases, in which a complete
understanding on the atomic level was achieved.
The Laboratory of Industrial Chemistry performs fundamental research in
the area of heterogeneous catalysis and aims to develop catalysts based
on mechanistic insight. The scientific challenge is the elucidation of
the reactions on the atomic level and
their interplay with the complex surface chemistry of heterogeneous
catalysts, which usually consist of many phases and components, often
present as nanoparticles or as X-ray amorphous layers.
The examined reactions belong to industrial redox chemistry.
Reduction catalysis comprises methanol synthesis, Fischer-Tropsch
synthesis, or the synthesis of higher alcohols. Oxidation catalysis
focuses on the selective oxidation of propene and methanol, the
oxidative dehydrogenation of hydrocarbons, or the selective oxidation
of alcohols in the gas phase and in the liquid phase. Recently, we
entered the fields of
electrocatalysis and heterogeneous photocatalysis.
oxidation and electrocatalysis require a deeper understanding of
For the synthesis of catalysts a large repertoire of methods
available including chemical vapor deposition, spray drying
and precipitation performed in a cascade of micromixers. In
the catalytic growth and surface modification of multiwalled carbon
nanotubes (CNTs) has become a major topic due to the numerous
applications of CNTs in electrocatalysis. All the necessary
routine techniques for catalyst characterization are
available with a strong focus on sorption techniques.
For improving the catalysts we first of all
study steady-state kinetics. Numerous continuously operated
flow set-ups with
online analytics are available, which allow to screen the parameter
space efficiently under full computer control using LabVIEW. The role
of the various elementary steps is investigated by applying transient
kinetic methods such as temperature-programmed reactor operation,
and concentration steps, and using isotopes including SSITKA. For these
methods we strongly rely on fast online mass spectrometry. In
we try to gain as much spectroscopic information as possible using
mainly FTIR and photoelectron spectroscopy. Recently, static and
dynamic microcalorimetry have been developed into versatile
probe the surface properties quantitatively.
Our research contributes to the Collaborative Research
Center SFB 558
"Metal-substrate interactions in heterogeneous catalysis", the
Research Departments Interfacial
Systems Chemistry (IFSC), Materials Research,
the Center for
Electrochemical Sciences (CES), all at the
Ruhr-University Bochum, and to the Center
for Nanointegration Duisburg-Essen (CeNIDE).
Cu colloids in methanol synthesis: structrual changes driven by strong
metal-support interactions, S. Schimpf, A. Rittermeier, X.
Zhang, Z. Li, M. Spasova, M. van den Berg, M. Farle, Y. Wang, R.
Fischer, M. Muhler, ChemCatChem,
activity and stability of nitrogen-containing carbon nanotubes in the
oxygen reduction reaction, S. Kundu, T. C. Nagaiah, W.
Xia, Y. Wang, S. van Dommele, J. H. Bitter, M. Santa, G. Grundmeier, M.
Bron, W. Schuhmann, M.
Muhler, J. Phys. Chem. C,
highly efficient gas-phase route for the oxygen-functionalization of
carbon nanotubes based on nitric acid vapor, W. Xia, C.
Jin, S. Kundu, M. Muhler, Carbon,
surface area ZnO nanoparticles via a novel continuous precipitation
route, S. Kaluza, M. K. Schröter, R. Naumann
d'Alnoncourt, T. Reinecke, M. Muhler, Adv. Funct. Mater.,
to adsorption thermodynamics on heterogeneous surfaces using different
empirical energy distribution models, X. Xia, S. Litvinov,
strongly reducing conditions on strong metal-support interactions in
Cu/ZnO catalysts used for methanol synthesis, R. Naumann
Alnoncourt, X. Xia, J. Strunk, E. Löffler, O. Hinrichsen, M.
Muhler, Phys. Chem.
the oxidative amination of benzene with ammonia to aniline over NiO/ZrO2
as cataloreactant, N. Hoffmann, M. Muhler, Catal. Lett., 2005, 155-159
chemical vapor deposition of Pd(allyl)Cp as an atom-efficient route to
synthesize highly dispersed palladium nanoparticles on carbon nanofibers,
C. Liang, W. Xia, H. Soltani-Ahmadi, O. F.-K. Schlüter, R. A.
Fischer, M. Muhler, Chem.
the active state of supported ruthenium catalysts used for the
oxidation of carbon monoxide: Steady-state and transient kinetics
combined with in situ Infrared Spectroscopy, J.
Narkhede, L. Khodeir, E. Löffler, O. Hinrichsen, A. Birkner,
Over, M. Muhler, J.
Chem. B, 108, 2004,
the oxidative dehydrogenation of methanol over polycrystalline silver
using the temporal-analysis-of-products approach, A. C.
van Veen, O. Hinrichsen, M. Muhler, J. Catal., 2002, 209, 501-514
ammonia synthesis catalyst of the next generation: barium-promoted
ruthenium, H. Bielawa, O. Hinrichsen, A. Birkner, M.
Muhler, Angew. Chemie
Int. Ed., 2001,
role of monomeric vanadyl species in toluene adsorption and oxidation
on V2O5/TiO2 catalysts: a Raman and in situ
DRIFTS study, S. Besselmann, E. Löffler, M.
Muhler, J. Mol. Catal.
A: Chem. 2000,
162 , 393-403