[{"title":"Room temperature CO oxidation catalysed by supported Pt nanoparticles revealed by solid-state NMR and DNP spectroscopy","doi":"10.1039/c9cy00684b","date_updated":"2026-02-17T16:16:33Z","author":[{"last_name":"Klimavicius","full_name":"Klimavicius, V.","first_name":"V."},{"first_name":"S.","full_name":"Neumann, S.","last_name":"Neumann"},{"first_name":"S.","full_name":"Kunz, S.","last_name":"Kunz"},{"first_name":"Torsten","id":"118165","full_name":"Gutmann, Torsten","last_name":"Gutmann"},{"full_name":"Buntkowsky, G.","last_name":"Buntkowsky","first_name":"G."}],"date_created":"2026-02-07T15:47:21Z","volume":9,"year":"2019","citation":{"ama":"Klimavicius V, Neumann S, Kunz S, Gutmann T, Buntkowsky G. Room temperature CO oxidation catalysed by supported Pt nanoparticles revealed by solid-state NMR and DNP spectroscopy. <i>Catalysis Science &#38; Technology</i>. 2019;9(14):3743–3752. doi:<a href=\"https://doi.org/10.1039/c9cy00684b\">10.1039/c9cy00684b</a>","chicago":"Klimavicius, V., S. Neumann, S. Kunz, Torsten Gutmann, and G. Buntkowsky. “Room Temperature CO Oxidation Catalysed by Supported Pt Nanoparticles Revealed by Solid-State NMR and DNP Spectroscopy.” <i>Catalysis Science &#38; Technology</i> 9, no. 14 (2019): 3743–3752. <a href=\"https://doi.org/10.1039/c9cy00684b\">https://doi.org/10.1039/c9cy00684b</a>.","ieee":"V. Klimavicius, S. Neumann, S. Kunz, T. Gutmann, and G. Buntkowsky, “Room temperature CO oxidation catalysed by supported Pt nanoparticles revealed by solid-state NMR and DNP spectroscopy,” <i>Catalysis Science &#38; Technology</i>, vol. 9, no. 14, pp. 3743–3752, 2019, doi: <a href=\"https://doi.org/10.1039/c9cy00684b\">10.1039/c9cy00684b</a>.","apa":"Klimavicius, V., Neumann, S., Kunz, S., Gutmann, T., &#38; Buntkowsky, G. (2019). Room temperature CO oxidation catalysed by supported Pt nanoparticles revealed by solid-state NMR and DNP spectroscopy. <i>Catalysis Science &#38; Technology</i>, <i>9</i>(14), 3743–3752. <a href=\"https://doi.org/10.1039/c9cy00684b\">https://doi.org/10.1039/c9cy00684b</a>","bibtex":"@article{Klimavicius_Neumann_Kunz_Gutmann_Buntkowsky_2019, title={Room temperature CO oxidation catalysed by supported Pt nanoparticles revealed by solid-state NMR and DNP spectroscopy}, volume={9}, DOI={<a href=\"https://doi.org/10.1039/c9cy00684b\">10.1039/c9cy00684b</a>}, number={14}, journal={Catalysis Science &#38; Technology}, author={Klimavicius, V. and Neumann, S. and Kunz, S. and Gutmann, Torsten and Buntkowsky, G.}, year={2019}, pages={3743–3752} }","mla":"Klimavicius, V., et al. “Room Temperature CO Oxidation Catalysed by Supported Pt Nanoparticles Revealed by Solid-State NMR and DNP Spectroscopy.” <i>Catalysis Science &#38; Technology</i>, vol. 9, no. 14, 2019, pp. 3743–3752, doi:<a href=\"https://doi.org/10.1039/c9cy00684b\">10.1039/c9cy00684b</a>.","short":"V. Klimavicius, S. Neumann, S. Kunz, T. Gutmann, G. Buntkowsky, Catalysis Science &#38; Technology 9 (2019) 3743–3752."},"intvolume":"         9","page":"3743–3752","publication_identifier":{"issn":["2044-4753"]},"issue":"14","keyword":["Chemistry","gamma-alumina","hydrogenation","silica","c-13","interactions","metal-catalysts","particle-size","platinum nanoparticles","sites","surface","water-gas shift"],"extern":"1","language":[{"iso":"eng"}],"_id":"63991","user_id":"100715","abstract":[{"lang":"eng","text":"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."}],"status":"public","type":"journal_article","publication":"Catalysis Science & Technology"},{"publication_identifier":{"issn":["2079-4991"]},"issue":"11","year":"2017","citation":{"chicago":"Vowinkel, S., S. Paul, Torsten Gutmann, and M. Gallei. “Free-Standing and Self-Crosslinkable Hybrid Films by Core-Shell Particle Design and Processing.” <i>Nanomaterials</i> 7, no. 11 (2017): 390. <a href=\"https://doi.org/10.3390/nano7110390\">https://doi.org/10.3390/nano7110390</a>.","ieee":"S. Vowinkel, S. Paul, T. Gutmann, and M. Gallei, “Free-Standing and Self-Crosslinkable Hybrid Films by Core-Shell Particle Design and Processing,” <i>Nanomaterials</i>, vol. 7, no. 11, p. 390, 2017, doi: <a href=\"https://doi.org/10.3390/nano7110390\">10.3390/nano7110390</a>.","ama":"Vowinkel S, Paul S, Gutmann T, Gallei M. Free-Standing and Self-Crosslinkable Hybrid Films by Core-Shell Particle Design and Processing. <i>Nanomaterials</i>. 2017;7(11):390. doi:<a href=\"https://doi.org/10.3390/nano7110390\">10.3390/nano7110390</a>","apa":"Vowinkel, S., Paul, S., Gutmann, T., &#38; Gallei, M. (2017). Free-Standing and Self-Crosslinkable Hybrid Films by Core-Shell Particle Design and Processing. <i>Nanomaterials</i>, <i>7</i>(11), 390. <a href=\"https://doi.org/10.3390/nano7110390\">https://doi.org/10.3390/nano7110390</a>","short":"S. Vowinkel, S. Paul, T. Gutmann, M. Gallei, Nanomaterials 7 (2017) 390.","bibtex":"@article{Vowinkel_Paul_Gutmann_Gallei_2017, title={Free-Standing and Self-Crosslinkable Hybrid Films by Core-Shell Particle Design and Processing}, volume={7}, DOI={<a href=\"https://doi.org/10.3390/nano7110390\">10.3390/nano7110390</a>}, number={11}, journal={Nanomaterials}, author={Vowinkel, S. and Paul, S. and Gutmann, Torsten and Gallei, M.}, year={2017}, pages={390} }","mla":"Vowinkel, S., et al. “Free-Standing and Self-Crosslinkable Hybrid Films by Core-Shell Particle Design and Processing.” <i>Nanomaterials</i>, vol. 7, no. 11, 2017, p. 390, doi:<a href=\"https://doi.org/10.3390/nano7110390\">10.3390/nano7110390</a>."},"intvolume":"         7","page":"390","date_updated":"2026-02-17T16:12:54Z","author":[{"first_name":"S.","last_name":"Vowinkel","full_name":"Vowinkel, S."},{"full_name":"Paul, S.","last_name":"Paul","first_name":"S."},{"first_name":"Torsten","full_name":"Gutmann, Torsten","id":"118165","last_name":"Gutmann"},{"full_name":"Gallei, M.","last_name":"Gallei","first_name":"M."}],"date_created":"2026-02-07T16:15:23Z","volume":7,"title":"Free-Standing and Self-Crosslinkable Hybrid Films by Core-Shell Particle Design and Processing","doi":"10.3390/nano7110390","type":"journal_article","publication":"Nanomaterials","abstract":[{"text":"The utilization and preparation of functional hybrid films for optical sensing applications and membranes is of utmost importance. In this work, we report the convenient and scalable preparation of self-crosslinking particle-based films derived by directed self-assembly of alkoxysilane-based cross-linkers as part of a core-shell particle architecture. The synthesis of well-designed monodisperse core-shell particles by emulsion polymerization is the basic prerequisite for subsequent particle processing via the melt-shear organization technique. In more detail, the core particles consist of polystyrene (PS) or poly(methyl methacrylate) (PMMA), while the comparably soft particle shell consists of poly(ethyl acrylate) (PEA) and different alkoxysilane-based poly(methacrylate)s. For hybrid film formation and convenient self-cross-linking, different alkyl groups at the siloxane moieties were investigated in detail by solid-state Magic-Angle Spinning Nuclear Magnetic Resonance (MAS, NMR) spectroscopy revealing different crosslinking capabilities, which strongly influence the properties of the core or shell particle films with respect to transparency and iridescent reflection colors. Furthermore, solid-state NMR spectroscopy and investigation of the thermal properties by differential scanning calorimetry (DSC) measurements allow for insights into the cross-linking capabilities prior to and after synthesis, as well as after the thermally and pressure-induced processing steps. Subsequently, free-standing and self-crosslinked particle-based films featuring excellent particle order are obtained by application of the melt-shear organization technique, as shown by microscopy (TEM, SEM).","lang":"eng"}],"status":"public","_id":"64053","user_id":"100715","keyword":["Materials Science","Science & Technology - Other Topics","solid-state nmr","spectroscopy","catalysts","colloidal crystals","colloids","cross-linking","elastomeric opal films","emulsion polymerization","gamma-methacryloxypropyltrimethoxysilane","hybrid films","melt-shear organization","nanoparticles","particle","photons","polymers","processing","self-assembly","transition"],"extern":"1","language":[{"iso":"eng"}]},{"status":"public","abstract":[{"lang":"eng","text":"Coordinatively unsaturated sites (CUS) present a key feature of alumina based catalysts as they are believed to act as Lewis-acid sites in heterogeneously catalyzed reactions. In the present study, the direct observation of active species on a fluoride-doped aluminum oxide catalyst is demonstrated. This new fluoride-doped aluminum oxide exhibits strong Lewis-acid sites and superior catalytic activity as compared to gamma-Al2O3. To emphasize the labile state of Lewis-acid sites, two distinctive states of the catalysts surface are addressed using H-1-Al-27 cross polarization (CP) MAS NMR. On the one hand, the highly dehydrated and active state after calcination at 700 degrees C and on the other hand the rehydrated and catalytically inactive surface (produced by contact to air) are probed. These experiments revealed the presence of significant amounts of coordinatively unsaturated sites in the form of 4-and 5-fold coordinated Al-sites on the highly dehydrated surface. In contrast to this, the rehydrated sample exhibited a severely restructured surface caused by the chemisorption of H2O which is ’constituted in a manner that was proposed in earlier models for gamma-Al2O3 surfaces."}],"publication":"Journal of Physical Chemistry C","type":"journal_article","language":[{"iso":"eng"}],"extern":"1","keyword":["al-27 nmr","characterization","Chemistry","cross-polarization","dynamic nuclear-polarization","eta-alumina","gamma-alumina","hydroxy fluorides","ions","Materials Science","pentacoordinated al3+","Science & Technology - Other Topics","solid-state nmr","spectroscopic","structural insights"],"user_id":"100715","_id":"63920","intvolume":"       121","page":"12206–12213","citation":{"apa":"Ahrem, L., Scholz, G., Gutmann, T., Calvo, B., Buntkowsky, G., &#38; Kemnitz, E. (2017). Direct Observation of Coordinatively Unsaturated Sites on the Surface of a Fluoride-Doped Alumina Catalyst. <i>Journal of Physical Chemistry C</i>, <i>121</i>(22), 12206–12213. <a href=\"https://doi.org/10.1021/acs.jpcc.7b02535\">https://doi.org/10.1021/acs.jpcc.7b02535</a>","short":"L. Ahrem, G. Scholz, T. Gutmann, B. Calvo, G. Buntkowsky, E. Kemnitz, Journal of Physical Chemistry C 121 (2017) 12206–12213.","mla":"Ahrem, L., et al. “Direct Observation of Coordinatively Unsaturated Sites on the Surface of a Fluoride-Doped Alumina Catalyst.” <i>Journal of Physical Chemistry C</i>, vol. 121, no. 22, 2017, pp. 12206–12213, doi:<a href=\"https://doi.org/10.1021/acs.jpcc.7b02535\">10.1021/acs.jpcc.7b02535</a>.","bibtex":"@article{Ahrem_Scholz_Gutmann_Calvo_Buntkowsky_Kemnitz_2017, title={Direct Observation of Coordinatively Unsaturated Sites on the Surface of a Fluoride-Doped Alumina Catalyst}, volume={121}, DOI={<a href=\"https://doi.org/10.1021/acs.jpcc.7b02535\">10.1021/acs.jpcc.7b02535</a>}, number={22}, journal={Journal of Physical Chemistry C}, author={Ahrem, L. and Scholz, G. and Gutmann, Torsten and Calvo, B. and Buntkowsky, G. and Kemnitz, E.}, year={2017}, pages={12206–12213} }","chicago":"Ahrem, L., G. Scholz, Torsten Gutmann, B. Calvo, G. Buntkowsky, and E. Kemnitz. “Direct Observation of Coordinatively Unsaturated Sites on the Surface of a Fluoride-Doped Alumina Catalyst.” <i>Journal of Physical Chemistry C</i> 121, no. 22 (2017): 12206–12213. <a href=\"https://doi.org/10.1021/acs.jpcc.7b02535\">https://doi.org/10.1021/acs.jpcc.7b02535</a>.","ieee":"L. Ahrem, G. Scholz, T. Gutmann, B. Calvo, G. Buntkowsky, and E. Kemnitz, “Direct Observation of Coordinatively Unsaturated Sites on the Surface of a Fluoride-Doped Alumina Catalyst,” <i>Journal of Physical Chemistry C</i>, vol. 121, no. 22, pp. 12206–12213, 2017, doi: <a href=\"https://doi.org/10.1021/acs.jpcc.7b02535\">10.1021/acs.jpcc.7b02535</a>.","ama":"Ahrem L, Scholz G, Gutmann T, Calvo B, Buntkowsky G, Kemnitz E. Direct Observation of Coordinatively Unsaturated Sites on the Surface of a Fluoride-Doped Alumina Catalyst. <i>Journal of Physical Chemistry C</i>. 2017;121(22):12206–12213. doi:<a href=\"https://doi.org/10.1021/acs.jpcc.7b02535\">10.1021/acs.jpcc.7b02535</a>"},"year":"2017","issue":"22","publication_identifier":{"issn":["1932-7447"]},"doi":"10.1021/acs.jpcc.7b02535","title":"Direct Observation of Coordinatively Unsaturated Sites on the Surface of a Fluoride-Doped Alumina Catalyst","volume":121,"date_created":"2026-02-07T08:56:18Z","author":[{"first_name":"L.","full_name":"Ahrem, L.","last_name":"Ahrem"},{"full_name":"Scholz, G.","last_name":"Scholz","first_name":"G."},{"last_name":"Gutmann","id":"118165","full_name":"Gutmann, Torsten","first_name":"Torsten"},{"first_name":"B.","last_name":"Calvo","full_name":"Calvo, B."},{"full_name":"Buntkowsky, G.","last_name":"Buntkowsky","first_name":"G."},{"full_name":"Kemnitz, E.","last_name":"Kemnitz","first_name":"E."}],"date_updated":"2026-02-17T16:19:24Z"}]