Synthesis of Nitrides via Magnesiothermic Reduction of Tantalum and Niobium Oxide Compounds
| Autor: | R. N. Osaulenko, V. Ya. Kuznetsov, V. M. Orlov |
|---|---|
| Rok vydání: | 2019 |
| Předmět: |
010302 applied physics
Materials science Magnesium General Chemical Engineering Inorganic chemistry Metals and Alloys Tantalum Niobium chemistry.chemical_element 02 engineering and technology 021001 nanoscience & nanotechnology 01 natural sciences Nitrogen Inorganic Chemistry Adsorption chemistry Specific surface area 0103 physical sciences Materials Chemistry Niobium oxide Leaching (metallurgy) 0210 nano-technology |
| Zdroj: | Inorganic Materials. 55:1118-1124 |
| ISSN: | 1608-3172 0020-1685 |
| Popis: | We have studied the feasibility of preparing tantalum and niobium nitrides by reducing Та2O5, Nb2O5, Mg4Та2O9, and Mg4Nb2O9 with magnesium vapor. The process was run in two steps: (1) reduction of the oxides at a temperature of 820°C and a residual argon pressure of 5 kPa in the reactor for 4 h and (2) nitridation of the reduction products in a nitrogen atmosphere at 820 and 900°C for 1–12 h. The phase composition of the powders after leaching out the magnesium oxide was determined on DRF-2 and DRON-4 X‑ray diffractometers. The specific surface area was determined by BET adsorption measurements on a Micromeritics TriStar II 3020 analyzer. When Ta2O5 was used as precursor, the nitridation product contained θ-TaN, e-TaN, and Ta2N. The use of Nb2O5 as a precursor led to the formation of face-centered cubic NbN, hexagonal close-packed NbN, Nb2N, and Nb4N3. The Mg4Ta2O9 and Mg4Nb2O9 reduction products did not absorb nitrogen. The results obtained are discussed in detail. |
| Databáze: | OpenAIRE |
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