• Article dans une revue

What do vanadium framework sites look like in redox model silicate zeolites?

Frederik Tielens, Monica Calatayud, Stanislaw Dzwigaj, Michel Che

Ab initio periodic DFT Calculations on the structural and energy properties of different model vanadium framework sites in vanadium-substituted zeolites containing sodalite cavities are presented and related to experimental FTIR measurements on V containing SiBEA zeolite. The vanadium framework…

Microporous and Mesoporous Materials, 2009, 119 (1-3), pp.137-143. ⟨10.1016/j.micromeso.2008.10.007⟩. ⟨hal-01361361⟩

• Article dans une revue

Nature of vanadium species in V substituted zeolites: A combined experimental and theoretical study

M. Trejda, M. Ziolek, S. Dzwigaj, Frederik Tielens

The nature of vanadium species in V substituted zeolites is determined by combined experimental (XRD, FTIR, DR UV-vis) and theoretical (periodic DFT Calculations) Study. The introduction of V ions in lattice sites of SiBEA zeolite is evidenced by XRD and FTIR spectroscopy. The state of vanadium is…

Catalysis Today, 2008, 139 (3), pp.221-226. ⟨10.1016/j.cattod.2008.04.007⟩. ⟨hal-01361370⟩

• Article dans une revue

Reactivity of gas-phase, crystal and supported V2O5 systems studied using density functional theory based reactivity indices

M. Calatayud, Frederik Tielens, F. de Proft

The existence of stable V2O5 compounds as gas-phase cluster, single crystal or as supported catalyst has motivated the present work aiming at characterizing the chemical reactivity of the different aggregated moieties. We apply the concepts of electrostatic potential and Fukui function, based on…

Chemical Physics Letters, 2008, 456 (1-3), pp.59-63. ⟨10.1016/j.cplett.2008.03.007⟩. ⟨hal-01361372⟩

• Article dans une revue

Remarkable effect of postsynthesis preparation procedures on catalytic properties of Ni-loaded BEA zeolites in hydrodechlorination of 1,2-dichloroethane

A. Śrębowata, R. Baran, D. Łomot, D. Lisovytskiy, T. Onfroy, S. Dzwigaj

Ni2.0SiBEA and Ni2.0HAlBEA zeolites were prepared by two different procedures: (i) a two-step postsynthesis method that consist of (1) creation of vacant T-atom sites by dealumination of HAlBEA (Si/Al = 17) with nitric acid and then (2) impregnation of as resulting SiBEA (Si/Al > 1300) with…

Applied Catalysis B: Environmental, 2014, 147, pp.208-220. ⟨10.1016/j.apcatb.2013.08.040⟩. ⟨hal-00960654⟩

• Ouvrages

Characterization of Solid Materials and Heterogeneous Catalysts: From Structure to Surface Reactivity, Volume 1&2

Che Michel, Védrine Jacques C.

This two-volume book provides an overview of physical techniques used to characterize the structure of solid materials, on the one hand, and to investigate the reactivity of their surface, on the other. Therefore this book is a must-have for anyone working in fields related to surface reactivity.…

2012, ⟨10.1002/9783527645329⟩. ⟨hal-01121673⟩

• Article dans une revue

Preparation of Highly Anisotropic Cobalt Ferrite/Silica Microellipsoids Using an External Magnetic Field

Sébastien Abramson, Vincent Dupuis, Sophie Neveu, Patricia Beaunier, David Montero

Magnetic cobalt ferrite/silica microparticles having both an original morphology and an anisotropic nanostructure are synthesized through the use of an external magnetic field and nanoparticles characterized by a high magnetic anisotropy. The association of these two factors implies that the ESE (…

Langmuir, 2014, 30 (30), pp.9190-200. ⟨10.1021/la501547q⟩. ⟨hal-01121597⟩

• Article dans une revue

Speciation of Ruthenium as a Reduction Promoter of Silica-Supported Co Catalysts: A Time-Resolved in Situ XAS Investigation

Jingping Hong, Eric Marceau, Andrei Y. Khodakov, Lucia Gaberová, Anne Griboval-Constant, Jean-Sébastien Girardon, Camille La Fontaine, Valérie Briois

Complete reduction of the metal phase in cobalt-containing catalysts is often difficult to reach and can be promoted by a small amount of noble metals. Because these costly promoters are introduced in a very low quantity, their speciation and their chemical interaction with cobalt have seldom been…

ACS Catalysis, 2015, 5 (2), pp.1273-1282. ⟨10.1021/cs501799p⟩. ⟨hal-01120477⟩

• Communication dans un congrès

Mechanochemical preparation of nanostructured mixed oxide catalysts for selective oxidation reactions

Sabine Valange, Ronan Behling, Gregory Chatel, Franck Launay

4th International Conference on Advanced Complex Inorganic Nanomaterials, Jul 2018, Namur, Belgium. ⟨hal-02002188⟩

• Article dans une revue

Exploring the reactivity of intraframework vanadium, niobium and tantalum sites in zeolitic materials using the molecular electrostatic potential

Frederik Tielens

The acid-base properties of group 5 zeolitic structures are discussed using the molecular electrostatic potential. The results point out that vanadium doped zeolites are less appropriate for electrophilic reactions, yielding minor basic character when they are compared with Nb or Ta doped zeolites…

Journal of Molecular Structure: THEOCHEM, 2009, 903 (1-3, SI), pp.23-27. ⟨10.1016/j.theochem.2008.09.045⟩. ⟨hal-01361358⟩

• Article dans une revue

Magnetic Traits in CoO‐Core@CoFe 2 O 4 ‐shell Like Nanoparticles

Nancy Flores-Martinez, Margot Roemer, Sarra Gam-Derouich, Patricia Beaunier, David Habrovsky, Souad Ammar

Antiferromagnetic (AF) CoO pseudo-single crystals 125±20 nm in diameter were prepared by forced hydrolysis in polyol and used as seeds to grow a poly- and nano-crystalline (5 nm in diameter) ferrimagnetic (F) CoFe2O4 shell. Transmission electron microscopy (TEM) showed a certain epitaxy between the…

ChemNanoMat, 2019, 5 (4), pp.514-524. ⟨10.1002/cnma.201800544⟩. ⟨hal-04022347⟩