Further characterization of the surface properties of the SiC particles through complementarity of updates XPS and IGC-ID techniques

In this work we demonstrated the necessity to complement the techniques XPS and IGC-ID to evaluate the surface properties of the SiC materials. We have studied four SiC materials with different particles sizes being 3 of them of a Si/C ratio close to the stoichiometry whereas for the fourth one, this ratio is 0.7, indicating an excess of C in the surface of the particles. The dispersive energy, gamma(d)(s), of these materials is 77.5, 64.0, 40.5 and 44.5 for the SiC sized 0.7, 1, 7 and 10 mu m, respectively. The lowest gamma(d)(s) values are found for the SiC than in XPS presented an excess of surface carbon. The acid constants k(A) are close to unity and in the case of the base constant k(B), they are found to be 1.1, 1.0, 0.4 and 1.1 for each above mentioned particle sized, being again the sample that presented the lowest k(B) value the sample that presented a particle size of 0.7. The SiC with an excess of surface C presents the lowest k(B)/k(A) ratio indicating that most part of the active sites are blocked by carbon atoms. (C) 2018 SECV. Published by Elsevier Espana, S.L.U.