Nanodomain Structure of Carbon‐Rich Silicon Carbonitride Polymer‐Derived Ceramics

Abstract

The presence of nanodomains in polymer‐derived ceramics constitutes one of the most intriguing features of this class of materials. In the present work, the nanostructure of novel carbon‐rich silicon carbonitride (SiCN) ceramics synthesized via thermolysis of poly(methylphenylsilylcarbodiimide), –[Ph(CH3) Si‐NCN]n–, at 1300°, 1500°, 1700°, and 2000°C is investigated by micro‐Raman spectroscopy, X‐ray powder diffractometry, and small‐angle X‐ray scattering (SAXS). The structural information obtained from these experimental methods is combined together with theoretical modeling of the SAXS data to obtain a detailed model of the temperature‐dependent evolution of nanodomains comprised of free carbon, SiC, and Si3N4 in SiCN‐based ceramics.

Electrochemical studies of carbon-rich polymer-derived SiCN ceramics as anode materials for lithium-ion batteries

“…In order to understand the extended cycling behavior of the studied samples, in particular the high capacity of sample 2 O, we correlate the electrochemical properties with the sample composition ( Table 2) and their structural properties as reported in references. 23,32 A characteristic feature of the carbon-rich polysilylcarbodiimide-derived SiCN ceramics is the presence of several types of nanodomains in the microstructure. The ceramics contain nanodomains comprised of amorphous phases, a-Si 3 N 4 , a-SiC and a-C, up to 1500 • C at which SiC starts to crystallize in the ß-polymorph (see Figs.…”

Texture and micro-nanostructure of porous silicon oxycarbide glasses prepared from hybrid materials aged in different solvents

“…SAXS has been widely used for the structural characterization of a wide range of materials including ceramics, polymers, sol-gel and colloidal systems. [23][24][25][26][27] Fig. 6 shows an example of the SAXS scattering curves of those materials where the solvent has been added after 120 h after the hybrid network synthesis.…”

Structure properties relationship in silicon oxycarbide glasses obtained by spark plasma sintering

“…In the case of the samples with Al 2 O 3 , the molar amount of C free phase is considerably higher than expected considering the La parameter and the results obtained in all the other samples. The general trend of increasing carbon nanodomain size with the C free phase is maintained when this reinforcement is used but the encountered small crystallite size suggests that there occurs a segregation of carbon inside the matrix [29,30].…”