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Selective Template Removal by Thermal Depolymerization to Obtain Mesostructured Molybdenum Oxycarbide |
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| Authors: | Martin Schieder Thomas Lunkenbein Carina Bojer Martin Dulle Julia vom Stein Gudrun Auffermann Tina Löbling Judith Schöbel Holger Schmalz Josef Breu |
| Institution: | 1. Lehrstuhl für Anorganische Chemie I, Universit?t Bayreuth, Universit?tsstr. 30, 95440 Bayreuth, Germany;2. Fritz‐Haber Institut der Max‐Planck Gesellschaft, Abteilung für Anorganische Chemie, Faradayweg 4–6, 14195 Berlin, Germany;3. Lehrstuhl für Physikalische Chemie I, Universit?t Bayreuth, Universit?tsstr. 30, 95440 Bayreuth, Germany;4. Max‐Planck Institut für Kohlenforschung, Abteilung für Heterogene Katalyse, Kaiser‐Wilhelm‐Platz 1, 45470 Mülheim a.d. Ruhr, Germany;5. Max‐Planck‐Institut für Chemische Physik fester Stoffe, N?thnitzer Stra?e 40, 01187 Dresden, Germany;6. Lehrstuhl für Makromolekulare Chemie II, Universit?t Bayreuth, Universit?tsstr. 30, 95440 Bayreuth, Germany |
| Abstract: | The carbon content of mesostructured organic‐inorganic hybrid material of a cylindrical block copolymer template of poly(2‐vinylpyridine)‐block‐poly(allyl methacrylate) (P2VP‐b‐PAMA) and ammonium paramolybdate (APM) could be reduced by thermal depolymerization. By calcination in vacuo at 320 °C the PAMA core can be completely removed while the remaining P2VP brush preserves the mesostructure. The P2VP‐APM composite can then be carburized in‐situ to MoOxCy in a second pyrolysis step without any additional carbon source but P2VP. The molybdenum oxycarbide nanotubes obtained, form hierarchically porous non‐woven structures, which were tested as catalyst in the decomposition of NH3. They proved to be catalytically active at temperatures above 450 °C. The activation energy was estimated from an Arrhenius Plot to be 127 kJ · mol–1. |
| Keywords: | Organic‐inorganic hybrid composites Template synthesis Template removal by depolymerization Non‐woven network Calcination |