[{"year":"2019","citation":{"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>","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.","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} }","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>","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>.","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>."},"intvolume":"         9","page":"3743–3752","publication_identifier":{"issn":["2044-4753"]},"issue":"14","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."},{"last_name":"Neumann","full_name":"Neumann, S.","first_name":"S."},{"last_name":"Kunz","full_name":"Kunz, S.","first_name":"S."},{"first_name":"Torsten","full_name":"Gutmann, Torsten","id":"118165","last_name":"Gutmann"},{"full_name":"Buntkowsky, G.","last_name":"Buntkowsky","first_name":"G."}],"date_created":"2026-02-07T15:47:21Z","volume":9,"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","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"},{"publication_identifier":{"issn":["1932-7447"]},"issue":"22","year":"2017","citation":{"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} }","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>.","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>","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>","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>."},"intvolume":"       121","page":"12206–12213","date_updated":"2026-02-17T16:19:24Z","date_created":"2026-02-07T08:56:18Z","author":[{"first_name":"L.","last_name":"Ahrem","full_name":"Ahrem, L."},{"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.","full_name":"Calvo, B.","last_name":"Calvo"},{"last_name":"Buntkowsky","full_name":"Buntkowsky, G.","first_name":"G."},{"full_name":"Kemnitz, E.","last_name":"Kemnitz","first_name":"E."}],"volume":121,"title":"Direct Observation of Coordinatively Unsaturated Sites on the Surface of a Fluoride-Doped Alumina Catalyst","doi":"10.1021/acs.jpcc.7b02535","type":"journal_article","publication":"Journal of Physical Chemistry C","abstract":[{"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.","lang":"eng"}],"status":"public","_id":"63920","user_id":"100715","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"],"language":[{"iso":"eng"}],"extern":"1"}]