Advanced ceramics are being investigated quite actively. The characterization of the materials used to make the ceramics is important to final product performance. We have previously reported an application of diffuse reflectance infrared Fourier transform (DRIFT) spectrometry to the determination of silicon dioxide (SiO2) in silicon carbide (SiC). The DRIFT technique was found to have a simpler application than that of transmission techniques, for the analysis of powdered solids, because DRIFT does not require the sample preparation of KBr disks or mineral oil mulls. However, the scattering caused by the analyte powder surface requires dilution of the SiC powder with KBr fine powder, to avoid distortion of the diffuse refractance spectrum. For quantitative work, this dilution requires accurate weighing and perfect mixing.
Akira Tsuge, Yoshinori Uwamino, and Toshio Ishizuka, "Determination of Silicon Dioxide in Silicon Carbide by Photoacoustic Infrared Fourier Transform Spectrometry," Appl. Spectrosc. 42, 168-170 (1988)