The C 1s and N 1s XPS spectra of samples prepared: in situ (nitrogen ion im
plantation to graphite); ex situ films with several ratio of C/N and C/N/O
and melomine (C3N6H6) have been studied. The C 1s spectra of the standard C
3N6H6 have splitting 3.3 eV that cannot be explain only by the chemical int
eraction; besides, in that compound the atoms of carbon have only one chemi
cal state. It is very problematic to identify the C 1s spectrum in terms on
ly of chemical shifts, but probably it is stipulated by some unknown physic
al properties of the CNx and CNxOy chemical compounds.
The problems of the synthesis of C3N4 are the difficulties of the formation
of stoichiometric compound and a monitoring of sp(3)-bonds of carbon atoms
as well. The possibilities of the C KVV Auger identification of sp(2)-sp(3
)-bonds in CNx and CNxOy are shown. (C) 1999 Elsevier Science S.A. All righ
ts reserved.