Novel insight into the chemical analysis of light elements in oxycarbides

Abstract

Pure powders of TiCxO(1-x) solid solution were synthesized through the carbothermal route. The chemical analysis of the light elements in the as-obtained TiCxO(1-x) oxycarbides powders were performed by Instrumented Gas Analysis (IGA). The cell parameters of the samples were determined with an accuracy of about 2% by means of X-ray powder diffraction and the internal standard method. As a result, a model correlating the cell parameters to the chemical composition was established. These reference TiCxO(1-x) oxycarbides powders were then sintered in order to obtain pellets of dense ceramics. After having determined that the sintering process does not change the chemical composition of the starting powder, chemical analysis of the different samples of the solid solution were successfully undertaken by Ion Beam Analysis techniques (IBA). The Nuclear Reaction Analysis (NRA) method -that was used to analyse light elements with very high sensitivity -was coupled with Rutherford Back Scattering (RBS) analysis in order to accurately determine the metallic over light elements ratio and to determine the stoichiometry of the phase on massive samples. Exhaustive simulations of the NRA spectra were performed and demonstrated that discrete compositions of the TiCxO(1-x) can be efficiently measured locally for bulk samples. Compared to IGA results, the relative amounts of carbon and oxygen of bulk materials were determined with a bias lower than 5%. This protocol being implemented for the TiCxO(1-x) system was then tested on HfCxO(1-x)with the same success.3

SiC-TiC nanocomposite for bulk solar absorbers applications: Effect of density and surface roughness on the optical properties

“…This increase in volume is consitent with the higher atomic radius of C compared to O. This result is in agreement with several studies about the evolution of lattice parameter of TiCxO(1-x) oxycarbide materials as a function of the composition [87,89].…”

Mechanical properties of submicronic and nanometric boron carbides obtained by Spark Plasma Sintering: Influence of B/C ratio and oxygen content

“…However, the remaining oxygen in the monoliths is involved in boron oxycarbide ceramics, B3.83CO0.04 and B4.59CO0.18 for HD and TK respectively. The position of the oxygen atom within the boron oxycarbide is unknown from the literature as it could fill a vacancy or, as for Ti-C-O or Zr-C-O, substitutes the carbon [40,41].…”

Zirconium oxycarbides and oxycarbonitrides: A review

“…IGA is a common method for C and N/O determination using infrared cells to analyze the combustion gases (CO, CO 2 , and NO x ). An accurate quantitative analysis of light elements at a local scale can be performed using nuclear reaction analysis coupled with Rutherford back scattering analysis, which gives the ratio of metallic to light elements, and makes it possible to determine the phase stoichiometry with good accuracy 99 …”