Publication Date:
2016-06-22
Description:
Graphene oxide, MPGO, was obtained by oxidation of graphite microparticles by a H 2 SO 4 /KMnO 4 /H 2 O 2 mixture followed by thermal exfoliation. Non-thermal plasma treatment of MPGO under SO 2 atmosphere resulted in the insertion of the oxidized intermediates only. Refluxing this material in CS 2 (46 °C) showed sulfur elimination and interconversion of the oxidized into non-oxidized intermediates with an energetic barrier of ΔG ‡ = 25.81 kcal mol −1 without decarboxylation . The episulfide content in modified MPGO increases with respect to the oxidized intermediates when increasing temperature. Modification of MPGO with SO 2 at 630 °C presented exclusively the non-oxidized intermediate . These results support the hypothesis that there are two major reactions with different energetic demand in the SO 2 reduction on carbons: desulfurization and decarboxylation . The selectivity of thiolysis and aminolysis towards the intermediates inserted in the MPGO matrix allowed the amino-thiolysis of a sample containing both intermediates with the insertion of the amino group on the episulfide site followed by an intramolecular thiolysis with double functionalization of the matrix. Copyright © 2016 John Wiley & Sons, Ltd. Refluxing in CS 2 graphene oxide containing only oxidized intermediates showed sulfur elimination and interconversion of the oxidized into non-oxidized episulfide intermediate without decarboxylation. The episulfide content in modified graphene oxide increases with respect to the oxidized intermediates with increasing temperature. There are two major reactions with different energetic demand in the sulfur dioxide reduction on carbons: desulfurization and decarboxylation. The selectivity of thiolysis and aminolysis towards the intermediates allowed the amino-thiolysis of a sample with the insertion of the amino group on the episulfide site followed by an intramolecular thiolysis, with double functionalization of the matrix.
Print ISSN:
0894-3230
Electronic ISSN:
1099-1395
Topics:
Chemistry and Pharmacology
,
Physics
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