@article{63991,
  abstract     = {{A series of 1 and 2 nm sized platinum nanoparticles (Pt-NPs) deposited on different support materials, namely, gamma-alumina (gamma-Al2O3), titanium dioxide (TiO2), silicon dioxide (SiO2) and fumed silica are investigated by solid-state NMR and dynamic nuclear polarization enhanced NMR spectroscopy (DNP). DNP signal enhancement factors up to 170 enable gaining deeper insight into the surface chemistry of Pt-NPs. Carbon monoxide is used as a probe molecule to analyze the adsorption process and the surface chemistry on the supported Pt-NPs. The studied systems show significant catalytic activity in carbon monoxide oxidation on their surface at room temperature. The underlying catalytic mechanism is the water-gas shift reaction. In the case of alumina as the support the produced CO2 reacts with the surface to form carbonate, which is revealed by solid-state NMR. A similar carbonate formation is also observed when physical mixtures of neat alumina with silica, fumed silica and titania supported Pt-NPs are studied.}},
  author       = {{Klimavicius, V. and Neumann, S. and Kunz, S. and Gutmann, Torsten and Buntkowsky, G.}},
  issn         = {{2044-4753}},
  journal      = {{Catalysis Science & Technology}},
  keywords     = {{Chemistry, gamma-alumina, hydrogenation, silica, c-13, interactions, metal-catalysts, particle-size, platinum nanoparticles, sites, surface, water-gas shift}},
  number       = {{14}},
  pages        = {{3743–3752}},
  title        = {{{Room temperature CO oxidation catalysed by supported Pt nanoparticles revealed by solid-state NMR and DNP spectroscopy}}},
  doi          = {{10.1039/c9cy00684b}},
  volume       = {{9}},
  year         = {{2019}},
}

@article{63956,
  abstract     = {{The synthesis of novel robust and stable iridium-based immobilized catalysts on silica-polymer hybrid materials (Si-PB-Ir) is described. These catalysts are characterized by a combination of 1D P-31 CP-MAS and 2D P-31-H-1 HETCOR and J-resolved multinuclear solid state NMR experiments. Different binding situations such as singly and multiply coordinated phosphines are identified. Density functional theory (DFT) calculations are performed to corroborate the interpretation of the experimental NMR data, in order to propose a structural model of the heterogenized catalysts. Finally, the catalytic activity of the Si-PB-Ir catalysts is investigated for the hydrogenation of styrene employing para-enriched hydrogen gas.}},
  author       = {{Gutmann, Torsten and Alkhagani, S. and Rothermel, N. and Limbach, H. H. and Breitzke, H. and Buntkowsky, G.}},
  issn         = {{0942-9352}},
  journal      = {{Zeitschrift Fur Physikalische Chemie-International Journal of Research in Physical Chemistry & Chemical Physics}},
  keywords     = {{Chemistry, dynamic nuclear-polarization, solid-state nmr, DFT, heterogeneous catalysis, hydrido complexes, hydrogenation, immobilized catalyst, inorganic hybrid, iridium, materials, mesoporous, molecular-orbital methods, PHIP, phosphine complexes, reusable catalysts, silica, solid-state-NMR, wilkinsons catalyst}},
  number       = {{3}},
  pages        = {{653–669}},
  title        = {{{P-31-Solid-State NMR Characterization and Catalytic Hydrogenation Tests of Novel heterogenized Iridium-Catalysts}}},
  doi          = {{10.1515/zpch-2016-0837}},
  volume       = {{231}},
  year         = {{2017}},
}

@article{64047,
  abstract     = {{A novel strategy for the immobilization of Wilkinson’s catalyst on silica nanoparticles is presented, employing pyridyl linkers as anchoring groups. The coordination binding of the catalyst to the pyridyl linker via ligand exchange of the trans-phosphine group is verified by 1 D and 2 D solid-state NMR spectroscopy. Catalytic activities are monitored by GC employing the hydrogenation of styrene as model reaction, and the leaching properties as well as the robustness of the catalyst are investigated. The resulting immobilized catalyst shows high catalytic activity, which is within a factor of three comparable to the homogeneous catalyst, and excellent stability in leaching tests. Finally, it is efficient to produce hyperpolarization in solution by employing parahydrogen-enriched hydrogen gas for hydrogenation.}},
  author       = {{Srour, Mohamad and Hadjiali, Sara and Sauer, Grit and Brunnengräber, Kai and Breitzke, Hergen and Xu, Yeping and Weidler, Heiko and Limbach, Hans-Heinrich and Gutmann, Torsten and Buntkowsky, Gerd}},
  journal      = {{ChemCatChem}},
  keywords     = {{heterogeneous catalysis, hydrogenation, immobilization, phosphane ligands, rhodium}},
  number       = {{21}},
  pages        = {{3409–3416}},
  title        = {{{Synthesis and Solid-State NMR Characterization of a Robust, Pyridyl-Based Immobilized Wilkinson’s Type Catalyst with High Catalytic Performance}}},
  doi          = {{10.1002/cctc.201600882}},
  volume       = {{8}},
  year         = {{2016}},
}