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Article dans une revue
Early stages of surface graphitization on nanodiamond probed by x-ray photoelectron spectroscopy
Abstract : Received 15 September 2011; revised 14 November 2011; published 19 December 2011 We have investigated the early stages of graphitization on detonation nanodiamond during sequential annealing treatments under vacuum using x-ray photoelectron spectroscopy. Two different temperature-dependent regimes were observed. Below 900 °C, the nanodiamond surface reconstructs into graphitic domain but does not alter the diamond core. Above 900 °C, graphitization, i.e., carbon hybridization changes from sp3 to sp2, occurs from the nanodiamond surface toward the diamond core. Graphitization is observed at much lower temperatures on nanodiamonds than on bulk diamond due to the high concentration of structural defects on their surface. These results indicate that low-temperature annealing under vacuum is an efficient method to uncouple surface and bulk graphitization. Hybrid nanocarbons formed in these conditions, constituted of a diamond core with a thin graphitic outer shell, may have interesting catalytic and chemical properties.
https://hal-mines-paristech.archives-ouvertes.fr/hal-00675687
Contributeur : Bibliothèque Umr7633 <>
Soumis le : jeudi 1 mars 2012 - 17:00:00
Dernière modification le : jeudi 24 septembre 2020 - 18:30:07
Contributeur : Bibliothèque Umr7633 <>
Soumis le : jeudi 1 mars 2012 - 17:00:00
Dernière modification le : jeudi 24 septembre 2020 - 18:30:07