Kinetics of C, N, and Xe release during the quasi-isothermal pyrolysis and subsequent oxidation of nanodiamond from the Orgueil CI meteorite
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Analysis of the C, N, and Xe release kinetics of intermediate-sized nanodiamond fraction from the Orgueil CI meteorite during isothermal pyrolysis conducted for the first time and subsequent oxidation indicates that (a) the rate of C, N, and Xe release at pyrolysis at a constant temperature decreases with time; (b) the relative amount of released Xe, which mostly has a normal isotopic composition (Xe-P3) at various pyrolysis time up to 800°C, is controlled, first of all, by the heating temperature, whereas the amount of N is controlled by both the temperature and heating time; and (c) prolonged pyrolysis notably modifies the distribution of nitrogen of normal (δ15N = 0) and anomalous (δ15N= −350‰) isotopic composition in diamond grains. The identified features of the C and N release kinetics are explained by differences in the binding energy of chemically adsorbed O with C atoms and the accommodation of the main amounts of N in extended defects of the crystal structure of nanodiamond. The major factors of the decrease in the Xe-P3 release rate during the isothermal pyrolysis of nanodiamond are either the differences between the Xe desorption parameters of the traps in graphite-like phases containing Xe-P3 or the differences between the radiation-induced defectiveness of grains of the population containing implanted Xe-P3. Our results led us to conclude that (1) meteoritic nanodiamond contains relatively low amounts of a phases carrying the P3 component of noble gases, regardless of the nature of this component, and (2) the population of nanodiamond grains containing most of isotopically anomalous nitrogen was produced at a high rate to preserve this nitrogen, first of all, at extended defects in the diamond crystal structure.
Keywordsnanodiamond meteorites carbon nitrogen xenon pyrolysis oxidation
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- 4.P. Hoppe, S. Amari, E. Zinner, and R. S. Lewis, “Isotopic Compositions of C, N, O, Mg, and Si, Trace Element Abundances, and Morphologies of Single Circumstellar Graphite Grains in Four Density Fractions from the Murchison Meteorite,” Geochim. Cosmochim. Acta 50, 4029–4056 (1995).CrossRefGoogle Scholar
- 6.A. V. Fisenko, A. B. Verchovsky, L. F. Semenova, and K. T. Pillinger, “Noble Gases in the Grain-Size Fractions of Presolar Diamond from the Boriskino CM2 Meteorite,” Geochem. Int. 42(8), 697–707 (2004).Google Scholar
- 7.A. V. Fisenko, A. B. Verchovsky, L. F. Semjonova, and C. T. Pillinger, “Interstellar Diamond: The Analysis Results for Carbon, Nitrogen, and Noble Gases in Different Grain-Size Fractions,” Solar Syst. Res. 34(1), 20–36 (2000).Google Scholar
- 8.A. B. Verchovsky, I. P. Wright, A. V. Fisenko, L. F. Semjonova, and C. T. Pillinger, “Ion Implantation Into Presolar Diamonds: Experimental Simulation,” J. Conf. Abstracts, Goldschmidt (2000). (Cambridge Publications, Oxford, 2000), CD ROM 1050.Google Scholar
- 9.G. R. Huss and R. S. Lewis, “Noble Gases in Presolar Diamonds. I: Three Distinct Components and Their Implications for Diamond Origin,” Meteoritics 29, 791–810 (1994).Google Scholar
- 16.A. V. Fisenko and L. F. Semjonova, “Some Features of Noble Gases Release from the Grain-Size Fractions of the Orgueil CI Meteorite Nanodiamonds,” Lunar Planet. Sci. 39, 1078 (2008).Google Scholar
- 18.A. V. Fisenko, L. F. Semjonova, A. S. Aronin, V. F. Tatsii, Yu. I. Mitrokhin, and L. N. Bol’sheva, “Size Separation of Interstellar Diamonds,” Geochem. Int. 36(5), 467–470 (1998).Google Scholar
- 19.I. P. Wright and C. T. Pillinger, “C Isotopic Analysis of Small Samples by Use of Stepped-Heating Extraction and Static Mass Spectrometry,” in New Frontiers in Stable Isotopic Research: Laser Probes, Ion Probes and Small Sample Analysis, Ed. by W. S Shanks and R. E. Criss, US Geol. Surv. Bull., no. 1890, 9–34 (1989).Google Scholar
- 20.A. B. Verchovsky, A. V. Fisenko, L. F. Semjonova, and C. T. Pillinger, “Heterogeneous Distribution of Xenon-HL within Presolar Diamonds,” Meteoritics Planet. Sci 32(4), A131–A132 (1997).Google Scholar
- 22.A. Braatz, F. Banhart, Th. Henning, and U. Ott, “Transformation of Meteoritic Diamonds to Graphitic Onions Upon Annealing,” Met. Planet. Sci. 34, A16–A17 (1999).Google Scholar
- 24.A. V. Fisenko, S. S. Russell, R. D. Ash, L. F. Semjonova, A. B. Verchovsky, C. T. Pillinger, “Isotopic Composition of Carbon and Nitrogen in the Diamonds from the Unequilibrated Ordinary Chondrite Krymka LL3.0,” Lunar Planet. Sci. 23, 363–364 (1992).Google Scholar