Role of nitrogen in the formation of HC-N films by CH(4)/N(2) barrier discharge plasma: aliphatic tendency.
We have studied the influence of nitrogen on the chemical properties of the hydrogenated carbon nitride (a-CN(x):H) film deposited by CH(4)/N(2) dielectric barrier discharge (DBD) plasma. X-ray photoelectron spectroscopy (XPS) indicates that carbon and nitrogen form an unpolarized covalent bond in these C-N(x) materials, and the observed chemical shift in the C 1s and N 1s binding energy is explained with respect to N 1s incorporation. Furthermore, the average nitrogen content (N/C approximately 0.76) in the films was systematically varied by changing the nitrogen partial pressure (CH(4)/N(2) approximately from 5:1 to 1:7) which is well supported by the elemental analysis. Fourier transform infrared (FTIR) absorption spectra exhibit significant changes in different C-N, C identical withN, and NH/OH molecular bands at higher nitrogen concentration in the film. The isonitrile and nitrile groups (-NC and -CN) are increased with the increase of deposition time. In addition, the elemental analysis, proton NMR, and thermolysis mass spectrum show that the composition of the film with the ratio CH(4)/N(2) approximately 1:1 is C, 67.68; H, 9.88; N, 16.53 (in wt %) and that the film is composed of polymers, probably containing linear chains which are cleaved off on heating in vacuum.
Majumdar
Abhijit
A
Institute of Physics, Ernst-Moritz-Arndt-University Greifswald, Felix-Hausdorff-Str. 6, 17489 Greifswald, Germany. majumdar@physik.uni-greifswald.de
Das
Gobind
G
Basvani
Kaleswara Rao
KR
Heinicke
Joachim
J
Hippler
Rainer
R
D004560:Electricity; D008567:Membranes, Artificial; D008697:Methane / Q000737:chemistry*; D009584:Nitrogen / Q000737:chemistry*; D013499:Surface Properties
D008567:Membranes, Artificial; D009584:Nitrogen; D008697:Methane