Experimental Realization of the Covalent Solid Carbon Nitride

American Association for the Advancement of Science (AAAS) - Tập 261 Số 5119 - Trang 334-337 - 1993
Chunming Niu1, Yuan Z. Lu2, Charles M. Lieber3
1Department of Chemistry , Harvard University , Cambridge , MA , 02138
2Materials Research Laboratory, Harvard University, Cambridge, MA 02138
3Department of Chemistry and Division of Applied Sciences, Harvard University, Cambridge, MA 02138

Tóm tắt

Pulsed laser ablation of graphite targets combined with an intense, atomic nitrogen source has been used to prepare C-N thin film materials. The average nitrogen content in the films was systematically varied by controlling atomic nitrogen flux. Rutherford backscattering measurements show that up to 40 percent nitrogen can be incorporated on average into these solids under the present reaction conditions. Photoelectron spectroscopy further indicates that carbon and nitrogen form an unpolarized covalent bond in these C-N materials. Qualitative tests indicate that the C-N solids are thermally robust and hard. In addition, strong electron diffraction is observed from crystallites within the films. Notably, analysis of these diffraction data show that the only viable structure for the C-N crystallites is that of β-C 3 N 4 , a material predicted theoretically to exhibit superhardness. The experimental synthesis of this new C-N material offers exciting prospects for both basic research and engineering applications.

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American Association for the Advancement of Science (AAAS)

Tập 261 Số 5119

334-337

Thông tin tác giả