@article{41271, author = {{Rabe, Volker and Frey, Wolfgang and Baro, Angelika and Laschat, Sabine and Bauer, Matthias and Bertagnolli, Helmut and Rajagopalan, Subramanian and Asthalter, Tanja and Roduner, Emil and Dilger, Herbert and Glaser, Thorsten and Schnieders, David}}, issn = {{1434-1948}}, journal = {{European Journal of Inorganic Chemistry}}, keywords = {{Inorganic Chemistry}}, number = {{31}}, pages = {{4660--4674}}, publisher = {{Wiley}}, title = {{{Syntheses, Crystal Structures, Spectroscopic Properties, and Catalytic Aerobic Oxidations of Novel Trinuclear Non‐Heme Iron Complexes}}}, doi = {{10.1002/ejic.200900516}}, volume = {{2009}}, year = {{2009}}, } @article{41270, author = {{Guillerm, Vincent and Gross, Silvia and Serre, Christian and Devic, Thomas and Bauer, Matthias and Férey, Gérard}}, issn = {{1359-7345}}, journal = {{Chem. Commun.}}, keywords = {{Materials Chemistry, Metals and Alloys, Surfaces, Coatings and Films, General Chemistry, Ceramics and Composites, Electronic, Optical and Magnetic Materials, Catalysis}}, number = {{5}}, pages = {{767--769}}, publisher = {{Royal Society of Chemistry (RSC)}}, title = {{{A zirconium methacrylate oxocluster as precursor for the low-temperature synthesis of porous zirconium(iv) dicarboxylates}}}, doi = {{10.1039/b914919h}}, volume = {{46}}, year = {{2009}}, } @article{41272, author = {{Di Noto, Vito and Boeer, Angelika B. and Lavina, Sandra and Muryn, Christopher A. and Bauer, Matthias and Timco, Grigore A. and Negro, Enrico and Rancan, Marzio and Winpenny, Richard E. P. and Gross, Silvia}}, issn = {{1616-301X}}, journal = {{Advanced Functional Materials}}, keywords = {{Electrochemistry, Condensed Matter Physics, Biomaterials, Electronic, Optical and Magnetic Materials}}, number = {{20}}, pages = {{3226--3236}}, publisher = {{Wiley}}, title = {{{Functional Chromium Wheel-Based Hybrid Organic-Inorganic Materials for Dielectric Applications}}}, doi = {{10.1002/adfm.200900600}}, volume = {{19}}, year = {{2009}}, } @article{41275, author = {{Bauer, Matthias and Bertagnolli, Helmut}}, issn = {{1439-4235}}, journal = {{ChemPhysChem}}, keywords = {{Physical and Theoretical Chemistry, Atomic and Molecular Physics, and Optics}}, number = {{13}}, pages = {{2197--2200}}, publisher = {{Wiley}}, title = {{{Towards X-Ray Absorption Spectroscopy in Real Time}}}, doi = {{10.1002/cphc.200900418}}, volume = {{10}}, year = {{2009}}, } @article{25975, abstract = {{The synthesis and characterization of ordered mesoporous In2O3 materials by structure replication from hexagonal mesoporous SBA-15 silica and cubic KIT-6 silica is presented. Variation of the synthesis parameters allows for different pore sizes and pore wall thicknesses in the products. The In2O3 samples turn out to be stable up to temperatures between 450 °C and 650 °C; such high thermal stability is necessary for their application as gas sensors. Test measurements show a high sensitivity to methane gas in concentrations relevant for explosion prevention. The sensitivity is shown to be correlated not only with the surface-to-volume ratio, but also with the nanoscopic structural properties of the materials.}}, author = {{Waitz, Thomas and Wagner, Thorsten and Sauerwald, Tilman and Kohl, Claus-Dieter and Tiemann, Michael}}, issn = {{1616-301X}}, journal = {{Advanced Functional Materials}}, pages = {{653--661}}, title = {{{Ordered Mesoporous In2O3: Synthesis by Structure Replication and Application as a Methane Gas Sensor}}}, doi = {{10.1002/adfm.200801458}}, year = {{2009}}, } @article{25977, abstract = {{We report a systematic study of the photoluminescence properties of ZnO nanostructures. In particular, mesoporous ZnO powders of varying surface-to-mass ratio are investigated and compared to a bulk reference. At low temperatures the emission from higher-energy states is very pronounced and even dominant for samples with high surface-to-mass ratio.}}, author = {{Schwalm, Michael and Horst, Swantje and Chernikov, Alexej and Rühle, Wolfgang W. and Lautenschläger, Stephan and Klar, Peter J. and Meyer, Bruno K. and Waitz, Thomas and Tiemann, Michael and Chatterjee, Sangam}}, issn = {{1610-1634}}, journal = {{physica status solidi (c)}}, pages = {{542--545}}, title = {{{Time-resolved photoluminescence study of mesoporous ZnO nanostructures}}}, doi = {{10.1002/pssc.200880315}}, year = {{2009}}, } @article{25974, abstract = {{We present the preparation of a semiconductor gas sensor based on ordered mesoporous In2O3. The In2O3 was synthesized by structure replication procedure from cubic KIT-6 silica. A detailed analysis of the morphology of the mesoporous powders as well as of the prepared sensing layer will be shown. Unique properties arise from the synthesis method of structure replication such as well defined porosity in the mesoporous regime and nanocrystallites with high thermal stability up to 450 °C. These properties are useful for the application in semiconducting gas sensors. Test measurements show sensitivity to methane gas in concentrations relevant for explosion prevention.}}, author = {{Wagner, T. and Sauerwald, T. and Kohl, C.-D. and Waitz, T. and Weidmann, C. and Tiemann, Michael}}, issn = {{0040-6090}}, journal = {{Thin Solid Films}}, pages = {{6170--6175}}, title = {{{Gas sensor based on ordered mesoporous In2O3}}}, doi = {{10.1016/j.tsf.2009.04.013}}, year = {{2009}}, } @article{25976, abstract = {{Halbleitende Metalloxid-Gassensoren werden sowohl im industriellen Bereich als auch im Haushalt zur Luftüberwachung verwendet. Die Funktionsweise basiert auf einer reversiblen Änderung des Sensorwiderstandes in Anwesenheit sowohl oxidierender als auch reduzierender Gase, die mit einfachen Mitteln gemessen werden kann. In diesem Artikel wird vorgestellt, wie sich die bei der Gasdetektion ablaufenden Vorgänge mit Hilfe des Ionosorptionsmodells in Kombination mit einem einfachen Festkörperbändermodell deuten lassen. Abschließend werden einfache, im Chemieunterricht zu realisierende Experimente mit Gassensoren präsentiert.}}, author = {{Waitz, Thomas and Tiemann, Michael}}, issn = {{0944-5846}}, journal = {{CHEMKON}}, pages = {{183--186}}, title = {{{Halbleitende Metalloxide als Gassensoren im Chemieunterricht}}}, doi = {{10.1002/ckon.200910099}}, year = {{2009}}, } @article{41276, author = {{Graziola, Francesco and Girardi, Fabrizio and Bauer, Matthias and Di Maggio, Rosa and Rovezzi, Mauro and Bertagnolli, Helmut and Sada, Cinzia and Rossetto, Gilberto and Gross, Silvia}}, issn = {{0032-3861}}, journal = {{Polymer}}, keywords = {{Polymers and Plastics, Materials Chemistry, Organic Chemistry}}, number = {{20}}, pages = {{4332--4343}}, publisher = {{Elsevier BV}}, title = {{{UV-photopolymerisation of poly(methyl methacrylate)-based inorganic–organic hybrid coatings and bulk samples reinforced with methacrylate-modified zirconium oxocluster}}}, doi = {{10.1016/j.polymer.2008.08.005}}, volume = {{49}}, year = {{2008}}, } @article{41277, author = {{Rill, Christoph and Bauer, Matthias and Bertagnolli, Helmut and Kickelbick, Guido}}, issn = {{0021-9797}}, journal = {{Journal of Colloid and Interface Science}}, keywords = {{Colloid and Surface Chemistry, Surfaces, Coatings and Films, Biomaterials, Electronic, Optical and Magnetic Materials}}, number = {{1}}, pages = {{179--186}}, publisher = {{Elsevier BV}}, title = {{{Microemulsion approach to neodymium, europium, and ytterbium oxide/hydroxide colloids—Effects of precursors and preparation parameters on particle size and crystallinity}}}, doi = {{10.1016/j.jcis.2008.05.008}}, volume = {{325}}, year = {{2008}}, } @article{41278, author = {{Akdogan, Yasar and Vogt, Christina and Bauer, Matthias and Bertagnolli, Helmut and Giurgiu, Liviu and Roduner, Emil}}, issn = {{1463-9076}}, journal = {{Physical Chemistry Chemical Physics}}, keywords = {{Physical and Theoretical Chemistry, General Physics and Astronomy}}, number = {{20}}, publisher = {{Royal Society of Chemistry (RSC)}}, title = {{{Platinum species in the pores of NaX, NaY and NaA zeolites studied using EPR, XAS and FTIR spectroscopies}}}, doi = {{10.1039/b718932j}}, volume = {{10}}, year = {{2008}}, } @article{41279, author = {{Wu, Jin-Ming and Antonietti, Markus and Gross, Silvia and Bauer, Matthias and Smarsly, Bernd M.}}, issn = {{1439-4235}}, journal = {{ChemPhysChem}}, keywords = {{Physical and Theoretical Chemistry, Atomic and Molecular Physics, and Optics}}, number = {{5}}, pages = {{748--757}}, publisher = {{Wiley}}, title = {{{Ordered Mesoporous Thin Films of Rutile TiO2 Nanocrystals Mixed with Amorphous Ta2O5}}}, doi = {{10.1002/cphc.200700679}}, volume = {{9}}, year = {{2008}}, } @article{25980, abstract = {{Mesoporous SBA-15 (space group p6mm), KIT-6 (Ia3d) and KIT-5 (Fm3m) silicas, exhibiting different 2-D and 3-D channel- or cage-like pore structure and pore dimensions have been used as supports for iron oxide nanoparticles. The iron modification of the silica was performed according to a frequently used impregnation technique from aqueous iron nitrate solution. The materials were characterized by nitrogen physisorption, X-ray diffraction, TEM–EDX, Moessbauer spectroscopy, and temperature-programmed reduction (TPR) and tested in the catalytic decomposition of methanol. It is established that the location and dispersion of iron oxide nanoparticles are affected by the pore topology of the support. The most homogeneously dispersed iron oxide nanoparticles are observed using silica host matrix exhibiting a 3-D channel-like structure and pore diameters about 7 nm, and the thus-obtained composites exhibit high catalytic activity and selectivity in methanol decomposition to CO and hydrogen. For all the samples, characterized with a low mesopore volume and small pore diameters/pore entrances, the formation of larger iron oxide particles, mainly located on the outer surface, is observed. Inhomogeneously dispersed iron oxide particles with a large fraction of isolated, strongly interacting with the support, iron species, and possessing low catalytic activity and usually high selectivity to methane, are found for the silicas with relatively larger pores/pore entrances.}}, author = {{Tsoncheva, Tanya and Rosenholm, Jessica and Linden, Mika and Kleitz, Freddy and Tiemann, Michael and Ivanova, Ljubomira and Dimitrov, Momtchil and Paneva, Daniela and Mitov, Ivan and Minchev, Christo}}, issn = {{1387-1811}}, journal = {{Microporous and Mesoporous Materials}}, pages = {{327--337}}, title = {{{Critical evaluation of the state of iron oxide nanoparticles on different mesoporous silicas prepared by an impregnation method}}}, doi = {{10.1016/j.micromeso.2007.10.005}}, year = {{2008}}, } @article{25979, abstract = {{Various measures to optimise the impregnation of mesoporous CMK-3 carbon and SBA-15 silica matrices with metal nitrates for the synthesis of mesoporous metal oxides by structure replication are investigated. The effect of surface modification of the matrix pores, the choice of a solvent with suitable polarity, and the concentration of the metal nitrate solution are studied in detail. The efficiency of pore loading is monitored by nitrogen physisorption measurements. The creation of polar functions at the pore surface of CMK-3 carbon is shown to increase the impregnation efficiency substantially while maximizing the pore wall polarity of SBA-15 silica by increasing the amount of free silanol groups does not have any significant impact. The choice of a less polar solvent (THF instead of water) has a positive effect on the wettability of CMK-3 carbon in the first impregnation cycle but turns out to be disadvantageous in the second cycle; a similar trend is observed for variation of the metal salt concentration.}}, author = {{Roggenbuck, Jan and Waitz, Thomas and Tiemann, Michael}}, issn = {{1387-1811}}, journal = {{Microporous and Mesoporous Materials}}, pages = {{575--582}}, title = {{{Synthesis of mesoporous metal oxides by structure replication: Strategies of impregnating porous matrices with metal salts}}}, doi = {{10.1016/j.micromeso.2007.12.018}}, year = {{2008}}, } @article{25982, abstract = {{Iron (III) containing nanoparticles with superparamagnetic behaviour are prepared via deposition on various mesoporous supports (MgO, CeO2 and SBA-15). XRD, TEM-EDX, N2 physisorption, FTIR, and Moessbauer spectroscopy are used for their characterization. The reductive properties and catalytic behaviour in methanol decomposition of the materials are also studied. Depending on the chemical nature of the support, the predominant formation of: isolated iron species, strongly interacting with the support (for SBA-15), mixture of hematite and binary MgFe2O4 nanoparticles (for MgO) or almost homogeneously dispersed hematite particles (for CeO2) are observed. The state of iron species strongly affects their catalytic properties. The favorable effect of the support mesoporosity on the catalytic activity is most pronounced for the iron modified CeO2.}}, author = {{Tsoncheva, Tanya and Roggenbuck, Jan and Tiemann, Michael and Ivanova, Lyubomira and Paneva, Daniela and Mitov, Ivan and Minchev, Christo}}, issn = {{1387-1811}}, journal = {{Microporous and Mesoporous Materials}}, pages = {{339--346}}, title = {{{Iron oxide nanoparticles supported on mesoporous MgO and CeO2: A comparative physicochemical and catalytic study}}}, doi = {{10.1016/j.micromeso.2007.06.021}}, year = {{2008}}, } @inbook{25983, abstract = {{Nanoporous semiconducting metal oxide materials (In2O3, WO3) with uniform pore systems, large specific surface areas (80 m2 g−1), and pore-wall crystallinity were prepared by structure replication, using KIT-6 silica as a template. The products show improved properties as gas sensors (for methane or butanone) as compared to non-porous samples. In addition, porous WO3 samples with comparable porosity (prepared by conventional ‘soft templating’, using pluronic P123), which are amorphous on the atomic length scale show poorer gas sensitivity, indicating that crystallinity is a crucial factor in the sensing process.}}, author = {{Waitz, Thomas and Wagner, Thorsten and Kohl, Claus-Dieter and Tiemann, Michael}}, booktitle = {{Zeolites and related materials: Trends, targets and challenges, Proceedings of the 4th International FEZA Conference}}, issn = {{0167-2991}}, title = {{{New mesoporous metal oxides as gas sensors}}}, doi = {{10.1016/s0167-2991(08)80227-3}}, year = {{2008}}, } @article{25981, abstract = {{The growth of ZnS nanoparticles during precipitation from aqueous solution is studied by in situ stopped-flow UV absorption spectroscopy at temperatures between 283 and 323 K. Particle growth is marked by substantial ripening during the first 60 ms. Kinetic data suggest that a ripening mechanism by coalescence (oriented attachment) is predominant over Ostwald ripening, although the latter seems to coexist to a significant degree at early temporal stages, predominantly at low temperatures.}}, author = {{Tiemann, Michael and Marlow, Frank and Hartikainen, Juha and Weiss, Özlem and Lindén, Mika}}, issn = {{1932-7447}}, journal = {{The Journal of Physical Chemistry C}}, pages = {{1463--1467}}, title = {{{Ripening Effects in ZnS Nanoparticle Growth}}}, doi = {{10.1021/jp077729f}}, year = {{2008}}, } @article{25978, abstract = {{In recent years, a lot of research activity has focused on the synthesis of new ordered porous materials by utilization of porous matrices as templates. Since the matrices are themselves created by templating procedures, the entire process can be envisaged as “repeated templating”. This review describes recent conceptual developments in the field of structure replication and summarizes the large number of publications on new functional materials prepared by this method.}}, author = {{Tiemann, Michael}}, issn = {{0897-4756}}, journal = {{Chemistry of Materials}}, pages = {{961--971}}, title = {{{Repeated Templating}}}, doi = {{10.1021/cm702050s}}, year = {{2008}}, } @inbook{25984, abstract = {{Mesoporous ceria was synthesized by using both CMK-3 carbon and SBA-15 silica as structure matrices. All products exhibit uniform mesopores with diameters of 5-6 nm in a two-dimensional periodic arrangement in addition to varying amounts of interparticle porosity. The gas sensing properties (methane detection) of ordered mesoporous ceria was compared to a non-porous sample.}}, author = {{ROGGENBUCK, JAN and Tiemann, Michael}}, booktitle = {{Nanoporous Materials}}, title = {{{Mesoporous Ceria by Structure Replication from Various Porous Matrices}}}, doi = {{10.1142/9789812779168_0019}}, year = {{2008}}, } @article{41281, author = {{Bauer, Matthias and Müller, Sonja and Kickelbick, Guido and Bertagnolli, Helmut}}, issn = {{1144-0546}}, journal = {{New Journal of Chemistry}}, keywords = {{Materials Chemistry, General Chemistry, Catalysis}}, number = {{11}}, publisher = {{Royal Society of Chemistry (RSC)}}, title = {{{The structures of the precursor Hf(OnBu)4 and its modification in solution: EXAFS-investigation in combination with XANES- and IR-spectroscopy}}}, doi = {{10.1039/b707079a}}, volume = {{31}}, year = {{2007}}, }