Methyldichloroborane Evidenced as an Intermediate in the Chemical Vapour Deposition Synthesis of Boron Carbide
| Autor: | Jean-Marc Leyssale, Guillaume Reinisch, Georges Chollon, S. Patel, Nathalie Bertrand, Gerard L. Vignoles, Alotta D |
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| Přispěvatelé: | Laboratoire des Composites Thermostructuraux (LCTS), Université de Bordeaux (UB)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut de Chimie du CNRS (INC)-Snecma-SAFRAN group-Centre National de la Recherche Scientifique (CNRS) |
| Jazyk: | angličtina |
| Rok vydání: | 2011 |
| Předmět: |
Materials science
Biomedical Engineering Halide chemistry.chemical_element Bioengineering 02 engineering and technology Chemical vapor deposition Boron carbide 01 natural sciences 7. Clean energy Carbide Chemical kinetics chemistry.chemical_compound General Materials Science Metalorganic vapour phase epitaxy Boron ComputingMilieux_MISCELLANEOUS 010405 organic chemistry General Chemistry 021001 nanoscience & nanotechnology Condensed Matter Physics 0104 chemical sciences [CHIM.THEO]Chemical Sciences/Theoretical and/or physical chemistry chemistry Chemical engineering Chemical vapor infiltration 0210 nano-technology |
| Zdroj: | Journal of Nanoscience and Nanotechnology Journal of Nanoscience and Nanotechnology, American Scientific Publishers, 2011, 11 (9), pp.8323-8327. ⟨10.1166/jnn.2011.5105⟩ Journal of Nanoscience and Nanotechnology, 2011, 11 (9), pp.8323-8327. ⟨10.1166/jnn.2011.5105⟩ |
| ISSN: | 1533-4880 |
| DOI: | 10.1166/jnn.2011.5105⟩ |
| Popis: | The most recent ceramic-matrix composites (CMC) considered for long-life applications as thermostructural parts in aerospace propulsion contain, among others, boron-rich phases like boron carbide. This compound is prepared by thermal Chemical Vapour Infiltration (CVI), starting from precursors like boron halides and hydrocarbons. We present a study aiming at a precise knowledge of the gas-phase composition in a hot-zone LPCVD reactor fed with BCl3, CH4 and H2, which combines experimental and theoretical approaches. This work has brought strong evidences of the presence of Methydichloroborane (MDB, BCl2CH3) in the process. It is demonstrated that this intermediate, the presence of which had never been formally proved before, appears for processing temperatures slightly lower than the deposition temperature of boron carbide. The study features quantum chemical computations, which provide several pieces of information like thermochemical and kinetic data, as well as vibration and rotation frequencies, reaction kinetics computations, and experimental gas-phase characterization of several species by FTIR, for several processing parameter sets. The main results are presented, and the place of MDB in the reaction scheme is discussed. |
| Databáze: | OpenAIRE |
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