Enhanced Thermal Oxidation Stability of Reduced Graphene Oxide by Nitrogen Doping
- Scientific Highlights 17 September 2014 6723 hits
Stefania Sandoval, Nitesh Kumar, Dr. A. Sundaresan, Prof. C. N. R. Rao*, Prof. Amparo Fuertes and Dr. Gerard Tobias*.
Chemistry - A European Journal, Volume 20, Issue 38, pages 11999–12003, September 15, 2014
Nitrogen-doped reduced graphene oxide (N-doped RGO) samples with a high level of doping, up to 13 wt. %, have been prepared by annealing graphene oxide under a flow of pure ammonia. The presence of nitrogen within the structure of RGO induces a remarkable increase in the thermal stability against oxidation by air. The thermal stability is closely related with the temperature of synthesis and the nitrogen content. The combustion reaction of nitrogen in different coordination environments (pyridinic, pyrrolic, and graphitic) is analyzed against a graphene fragment (undoped) from a thermodynamic point of view. In agreement with the experimental observations, the combustion of undoped graphene turns out to be more spontaneous than when nitrogen atoms are present.