Abstract
The ultrathin peroxoantimonate coating of graphene oxide from hydrogen peroxide-rich solutions of hydroxoantimonate is demonstrated. An amorphous 1-2 nm Sb (V) oxide film is formed and can be further crystallized by exposure to an electron beam to give a 2-5 nm thick supported Sb 6O 13 particulate coating. Heat treatment of the peroxoantimonate yielded different crystalline oxides, whereas in the presence of the graphene support only trigonal Sb (0) was produced by heat treatment in vacuum or an argon atmosphere. The graphene oxide support is essential for the formation of the Sb (0) phase and even in air a substantial elemental antimony was obtained. Whereas heat treatment of uncoated graphene oxide in an inert atmosphere produces reduced graphene oxide, the antimony oxide coated graphene oxide is not reduced by the heat treatment. Only after the supported antimony oxide is reduced to give the trigonal Sb (0) phase the graphene oxide was reduced by the heat treatment. The phases before and after the different heat treatments are characterized by electron and X-ray diffraction, thermal analysis, XPS studies, electron microscopy and wet chemistry.
| Original language | English |
|---|---|
| Pages (from-to) | 5463-5471 |
| Number of pages | 9 |
| Journal | Carbon |
| Volume | 50 |
| Issue number | 15 |
| DOIs | |
| State | Published - Dec 2012 |
Bibliographical note
Funding Information:This explanation however fails to explain two observations: a) GO was not reduced until the antimony oxide was fully reduced ( Fig. 8 ). Why would the occurrence of Eq. (3) limit the propagation of Eq. (1) ? b) The STEM image of Fig. 1 d clearly shows that the graphene support remains intact and continues to support the Sb nanocrystals after the heat treatment and the reduction of the antimony oxide. The later finding was also supported by the SAED studies of Sb supported graphene after the heat treatment ( Fig. S3 ). The figure shows that the two faint rings of GO electron diffraction remain after the heat treatment (in addition to the single crystal diffraction of the trigonal Sb).